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In agricultural land areas, no‐tillage (NT) farming systems have been practiced to replace intensive tillage practices such as, moldboard plow (MP), chisel plow (CP), and other systems to improve many soil health indicators, and specifically to increase soil organic carbon (SOC) sequestration and reduce soil erosion. Numerous approaches to estimate the amounts and rates of SOC sequestration as a result of a switch to NT systems have been published, but there is a concern regarding protocol for assessing SOC especially for different tillage systems. Therefore, the objectives of this paper are to: (i) define and understand concepts of SOC sequestration, (ii) quantify SOC distribution and the methodology of measurements, (iii) address soil spatial variability at field‐ or landscape‐scale for potential SOC sequestration, and (iv) consider proper field experimental design, including pretreatments baseline for SOC sequestration determination. For SOC sequestration to occur, as a result of a treatment applied to a land unit, all of the SOC sequestered must originate from the atmospheric CO2pool and be transferred into the soil humus through land unit plants, plant residues, and other organic solids. The SOC stock present in soil humus at end of a study must be greater than the pretreatment SOC stock levels in the same land unit. However, one should recognize that a continuity equation showing drawdown in atmospheric concentration of CO2may be difficult, if not impossible, to quantify. Therefore, SOC sequestration results of paired comparisons of NT to other conventional tillage systems with no pretreatments SOC baseline, and if the conventional system is not at a steady state, will likely be inaccurate where the potential for SOC loss exists in both systems. To unequivocally demonstrate that the SOC sequestration has occurred at a specific site, a temporal increase must be documented relative to pretreatment SOC content and linked attendant changes in soil properties and ecosystem services and functions with proper consideration given to soil spatial variability. Also, a standardized methodology that includes proper experimental design, pretreatment baseline, root zone soil depth consideration, and consistent method of SOC analysis must be used when determining SOC sequestration.

Introduction:Hyperglycemia at stroke onset worsens outcome and reduces the effectiveness of reperfusion therapies. Increased oxidative and mitochondrial injury likely contribute. To treat this mechanism, we synthesized (PEG)-ylated carbon nanoparticles (CNPs) from acid oxidation of activated charcoal (OAC) generating 3 nm discs, catalytic superoxide dismutase mimetics that protect mitochondrial complexes. Cellular uptake is rapid and delayed I.V. PEG-CNPs are highly protective in reversible MCAO in hyperglycemic rats. Hydrogen sulfide (H2S) is an essential gaseous transmitter with a narrow therapeutic index associated with many disorders e.g., diabetes. Its synthesis is influenced by radicals. Excess H2S is toxic to mitochondrial complex IV. H2S is endogenously oxidized to polysulfides (PS), potent antioxidants also needed for protein persulfidation. We hypothesized that OAC’s favorable redox potential will catalyze H2S oxidization to PS, acute hyperglycemia will increase H2S and PEG-OACs will blunt the increase.Methods:b.End3 brain endothelial and HEK293 cultured cells were employed. SSP4 fluorescence measured PS levels with increasing concentrations of PEG-OACs. AzMC fluorescence detected H2S levels in cells incubated in 100 mg/dL glucose media followed by glucose 500 mg/dL with or without PEG-OACs, first in normoxia followed by anoxia/normoxia.Results:PEG-OACs dose dependently increased cellular PS levels (Fig 1a). High glucose increased H2S levels especially during anoxia/normoxia (Fig 1b). PEG-OACs completely eliminated the glucose-induced increase in H2S (Fig 1c).Conclusions:Acute hyperglycemia increased H2S production especially under conditions mimicking ischemia/reperfusion, an effect eliminated by PEG-OACs. Because of mitochondrial toxicity, an H2S increase may contribute to worsened outcome in hyperglycemic stroke. These results suggest a new therapeutic target for this important cause of poor stroke outcome.

Most Illinois soil landscapes are nearly level and composed of somewhat poorly drained soils on slightly higher convex landscape positions and poorly drained soils on concave landscape positions. These soils are commonly on less than 1 slopes and are not thought to have water erosion and sediment deposition problems. A plot area near Monmouth, Illinois, was selected for study. The fly ash and soil organic C (SOC) content of Muscatune and Sable soils were determined. The crop sequence was corn and soybeans for the last 27 years, and plot area had been cultivated for the last 130 years. There is no tile drainage in the plot area. The primary objective of this research was to determine the extent Muscatune soil on 1 slope was eroded in the past 100 to 130 years of cultivation. The fly ash and SOC-rich sediment being transported to and deposited on the adjacent Sable soil in the same plot area were measured using a fly ash method. Fly ash is particulate matter resulting from high-temperature combustion of coal since 1910s and can be used as a time marker in upland soil erosion and depositional studies. For the 0- to 0.50-m layer, the Sable soil fly ash content is 19 higher and the SOC is similar (4 higher) to those of the Muscatune soil. The erosion rate, using the fly ash method, was 4.35 Mg ha−1year−1, which was higher than the calculated RUSLE2 erosion rate of 3.3 Mg ha−1year−1. Approximately 0.06 m of the thickness difference of 0.21 m between Sable and Muscatune A horizons was the result of erosion of the Muscatune soil and deposition on the Sable soil. The remaining difference was as a result of higher water table and saturated soil conditions for long periods.

The article focuses on the use of fly ash, a particulate matter resulting from high-temperature combustion of coal, in assessing the extent of sediment transport and deposition on a nearly level western Illinois landscapes. It informs that Illinois's soil landscapes are leveled and composed of poorly drained soils on higher convex and concave landscape positions. It states that fly ash can be used as a time marker in depositional studies and upland soil erosion.

Many factors, including land use, management history, soil type, climate, and soil landscape processes, affect the dynamics of soil organic carbon (SOC). The primary objective of this research was to determine the SOC level in a timberland of west-central Illinois and then to compare the level with the SOC levels in adjacent cropland and pastureland after 150 years of agricultural use. The SOC concentration of various soil layers, to a depth of 0.5 m, was measured. The timberland contained 68.3 Mg C ha−1in 2009. Results suggested that the cropland landscape retained 59.7 Mg C ha−1or 87 of the total SOC in the timberland on a volumetric basis after the last 150 years of cultivation and cropland use. Soil erosion and sediment transport resulted in some SOC being deposited in lower landscape positions but retained in landscape. The other 13 net loss of the SOC storage was either deposited in the water or released to the atmosphere. The last 90 years of pasture use increased the SOC of the site as a result of C loading in the form of manure, which resulted in increased SOC storage and offset all previous losses of SOC caused by cultivation, soil erosion, and aeration. The current pastureland had 34 more SOC than the timberland in 2009 and 53 more than the cropland. These results suggest that if west-central Illinois timberland soils were cleared and used for cropland, cultivation and subsequent soil erosion and transported C-rich sediment will result in SOC redistribution on landscape with greater SOC retention in lower landscape positions, with SOC being released to streams or to the atmosphere. However, if timberland is converted to pastureland, significant amounts of SOC and soil organic N (SON) would be stored in soil as humus. Conversion of timberland to cropland reduced SOC storage, and conversion to pastureland increased SOC storage and retention.

The article presents a study which determines the impacts of slope, land-use change, and erosion on soil organic carbon (SOC) storage and retention. Statistical Analysis System (SAS) computer software was use to examine the collected soils from cropland, sloping timberland, and pastureland which analyzed its position, elevation, and soil series for SOC. It shows that conversion of timberland to pastureland increased SOC storage and retention, and conversion to cropland reduced SOC storage.

The dynamics of soil organic carbon (SOC) are affected by many factors including land use, management history, soil type, climate, and soil landscape processes. The primary objective of this research was to compare the storage of SOC on sloping woodland and cropland landscapes of northwestern Illinois. The cropland area was cultivated using a moldboard plow system for 125 years, and then the primary tillage was changed to chisel plow for the last 25 years. The woodland area was never cleared or cultivated. The SOC concentrations of various soil layers, to a depth of 0.5 m, were measured. The woodland landscape had significantly higher SOC in the surface layers on all landscape segments than at the cultivated site. For both land uses, the subsurface layers had similar SOC levels. Results suggested that the cropland landscape retained 52% of the total SOC on a volumetric basis during the last 150 years of cultivation, soil erosion, and agricultural use. The other 48% of the SOC was either deposited in the water or released to the atmosphere. Results suggest that if mesic-frigid temperature line moved north because of climate change, then the current uncultivated forest soils would be used for cropland, and additional SOC will be released to either the stream or atmosphere and not maintained in soil even with a chisel plow system.

The article discusses a research study on the effect of land use change and soil erosion in upper Mississippi river on soil organic carbon (SOC) retention and greenhouse gas emissions. The research's main objective is to compare the storage of SOC on sloping woodland and cropland landscapes of northwestern Illinois. It measures the SOC concentrations of several soil layers.

The objective of this 20-year tillage study was to quantify the amount and rates of soil organic carbon (SOC) storage and retention as a result of a conversion to no-till (NT) or chisel plow (CP) tillage systems using the comparison method with moldboard plow (MP) tillage SOC data as baseline. The NT and CP plots did store and retain 8.4 Mg C ha−1and 0.6 Mg C ha−1more SOC in the soil than MP. That SOC amount was retained in the soil and not decomposed and re-emitted to the atmosphere as a result of cultivation or in the transported sediment moved off of the plots. However, no SOC sequestration occurred in the NT, CP, and MP plots because the SOC level of the plot area was higher at the start of the experiment than at the end of the study. Pretreatment SOC baseline of the plot area was used to determine NT, CP, and MP SOC sequestration or loss. The NT plots actually lost a total of −6.8 Mg C ha−1, the CP lost −15.1 Mg C ha−1, and the MP lost −15.2 Mg C ha−1during the 20-year study. Soil erosion and transport of SOC rich sediment off of the sloping plots contributed substantially (29%-39%) to these SOC losses. These findings suggest that determination of a pretreatment SOC baseline is essential in all tillage comparison studies to determine the amount and rate of SOC sequestration or loss.

An 8-year cover crop study was conducted in southern Illinois to evaluate the effects of conservation tillage systems on corn and soybean yields and for the maintenance and restoration of soil organic carbon (SOC) and soil productivity of previously eroded soils. In 2001, the no-till (NT), chisel plow, and moldboard plow (MP) treatment plots, which were replicated six times in a Latin square design, were split (with cover crop and without) on sloping, moderately well-drained, moderately eroded soil. The average corn and average soybean yields were similar for NT, chisel plow, and MP systems with and without cover crops. By 2009, the tillage zone, subsoil, and rooting zone of all treatments had similar SOC on a volume basis for the cover crop treatments as for the same tillage treatment without a cover crop. However, using the baseline 2000 SOC contents only, the NT with cover crops maintained most of the SOC levels in the topsoil and subsoil during the 8-year study, when the sediment was high in SOC and retained in the upland landscape by soil conservation practices, including border and filter strips and sod waterways adjacent to the plots, with and without cover crops. Soil carbon creation retention in the upland landscape was greatest for the MP treatments when sediments were retained by the soil conservation practices, which should reduce soil erosion and sediment rich in SOC being transported by overland flow into water and the eventual release of methane and carbon dioxide to the atmosphere.

The radio-cesium (cesium-137 137Cs) and technogenic magnetic tracer (magnetic fly-ash spheroids) methods for the quantitative assessment of erosion-deposition processes were compared on Illinois landscapes with both cultivated and uncultivated sites located near Springfield, IL. The objectives of this study were to determine (1) the variability of the 137Cs and fly-ash contents within a stable landscape position, (2) the distribution and amount of fly ash and radio-cesium present in soil profiles on cultivated and uncultivated landscapes (summit, upper sideslope, lower sideslope, and alluvial fan/floodplain); and (3) the extent of soil erosion and deposition at four landscape positions on cultivated and uncultivated transect sites using both the radio-cesium and technogenic magnetic tracer methods. On a stable site, the fly-ash method had significantly greater natural variability (40% vs. 27%) than the 137Cs method as a result of bioturbation. The fly-ash and 137Cs methods did provide consistent results for six of eight cultivated and uncultivated landscape positions. At the other two sites where significant deposition or erosion did occur before the 1960s, the amount of erosion loss was different. The applicable time period for the fly-ash method assessment of the erosion and deposition situation was during the last 150 years, whereas the 137Cs method only assessed the last 50years. Land use, vegetation, erosion, and deposition may have differed during the first 100 years (1860s-1960s) of European settlement from those of the last 50 years (1960s to present) at the cultivated and uncultivated sites. Any such impact, either deposition or erosion before the 1960s, would not be reflected in the 137Cs data but would be reflected in the fly-ash data.

Hypoxia contracts mammalian respiratory vessels and increases vascular resistance in respiratory tissues of many vertebrates. In systemic vessels these responses vary, hypoxia relaxes mammalian vessels and contracts systemic arteries from cyclostomes. It has been proposed that hypoxic vasoconstriction in cyclostome systemic arteries is the antecedent to mammalian hypoxic pulmonary vasoconstriction, however, phylogenetic characterization of hypoxic responses is lacking. In this study, we characterized the hypoxic response of isolated systemic and respiratory vessels from a variety of vertebrates using standard myography. Pre‐gill/respiratory (ventral aorta, afferent branchial artery, pulmonary artery) and post‐gill/systemic (dorsal and thoracic aortas, efferent branchial artery) from lamprey (Petromyzon marinus), sandbar shark (Carcharhinus plumbeus), yellowfin tuna (Thunnus albacares), American bullfrog (Rana catesbeiana), American alligator (Alligator mississippiensis), Pekin duck (Anas platyrhynchos domesticus), chicken (Gallus domesticus) and rat (Rattus norvegicus) were exposed to hypoxia at rest or during pre‐stimulation (elevated extracellular potassium, epinephrine or norepinephrine). Hypoxia produced a relaxation or transient contraction followed by relaxation in all pre‐gill vessels, except for contraction in lamprey, and vasoconstriction or tri‐phasic constriction‐dilation‐constriction in all pulmonary vessels. Hypoxia contracted systemic vessels from all animals except shark and rat and in pre‐contracted rat aortas it produced a transient contraction followed by relaxation. These results show that while the classic “systemic hypoxic vasodilation and pulmonary hypoxic vasoconstriction” may occur in the microcirculation, the hypoxic response of the vertebrate macrocirculation is quite variable. These findings also suggest that hypoxic vasoconstriction is a phylogenetically ancient response. J. Exp. Zool. 309A:55–63, 2008. © 2008 Wiley‐Liss, Inc.

Many factors including land use, management history, soil type, climate, and soil landscape processes affect the dynamics of soil organic C (SOC). The primary objective of this research was to compare the storage of SOC on sloping woodland and cropland landscapes of southern Illinois. The cropland area was previously cultivated between the 1880s and the 1930s, used for crop production with forages in crop rotation between the 1930s and the 1960s, and remained in hayland from the 1960s to 1989. Since 1989, row crops were grown on a yearly rotation system using conservation tillage practices. The woodland area was never cleared and farmed but part of the landscape was subjected to periodic grazing before the 1960s. The SOC concentration of various soil layers, to a depth of 1 m, was measured and expressed on both a gravimetric and volumetric basis. The woodland landscape had significantly higher SOC in the surface layer (0-0.05 m) on all 6 landscape segments; however, the 0.05- to 0.15-m layer in the cropland landscape contained significantly more SOC. The subsurface rooting zone SOC values varied by landscape segment for both land uses. Results suggested that the cropland landscape retained 95% of the total SOC on a volumetric basis during the last 130 years of agricultural use. The years with forages may have increased the SOC of the cropland site and help offset losses due to soil erosion and aeration as a result of tillage. The woodland and agricultural landscapes appear to have similar amounts of SOC when the crop rotations included forages, cover crops, conservation tillage, and contour farming. Results suggest that southern Illinois soils can be used for cropland with conservation practices and forages while still maintaining the SOC levels of woodland.

Hydrogen sulfide (H2S) vasoactivity has been observed in isolated vessels from all vertebrate classes, and its effects, which include constriction, dilation, and multiphasic responses, are both species- and vessel-specific. H2S is synthesized by mammalian and fish vessels, and because plasma H2S titers are also vasoactive in vitro, it is likely that H2S is a tonic effector of cardiovascular homeostasis in many vertebrates. Mechanisms of H2S vasoactivity in nonmammalian vertebrates have been limited to the trout where the triphasic relaxation–contraction–relaxation includes endothelium-dependent and -independent components, ATP-dependent K+ channels, and extracellular and intracellular Ca2+, all independent of cyclic GMP production. The observation that at least some H2S constrictory activity has been observed in all vertebrates except sharks suggests that H2S may have been an ancestral pressor gasotransmitter. However, the ability of H2S to serve as either (or both) an endothelium-independent constrictor or dilator, which is relatively unique among vasoregulatory molecules, is a feature that seems to have been exploited, for unknown reasons, by nearly all vertebrates. Aquatic vertebrates appear particularly vulnerable to H2S because of their intrinsically low blood pressure and the potential for increased H2S exposure from the environment.Antioxid. Redox Signal. 7, 804–812.

Relations were examined between configurations of Big Five Traits (Extraversion, Agreeableness, Conscientiousness, Neuroticism, Openness to Experience) and 16 fundamental motives (Social Contact, Curiosity, Honor, Power, Order, Idealism, Independence, Status, Vengeance, Romance, Family, Activity, Saving, Acceptance, Eating, Tranquility) in 138 university students (93 women, 45 men; Mage = 20.3 yr., SD= 4.5). Big Five traits were measured with the NEO-PI–R and motives were measured with the Reiss Profile of Fundamental Goals and Motivation Sensitivities. The traits were significantly related with all the motives (adjusted R2= .06 to .43) except Physical Activity. Four motives were related with only one trait and nine configurations of two or more traits were correlated with the remaining 11 motives. Total motive scores across all participants, an index of the strength of overall motivation, were positively correlated with Extraversion and Neuroticism and negatively with Agreeableness.

Provides information related to the tea-producing region in Assam, India. Description of geographical locations; Range of total harvests; Details of the fermentation process.

Looks into the development of the coffee trade practices in Yemen. Previous methods used in the transportation of coffee in Yemen; Beginning of the exportation of coffee from the country; Yemen legend dictating the spread of coffee in Europe; Descriptions of the country and its coffee harvests.

Features the coffee industry in Hawaii. History of coffee growing in the country; Ideal growing conditions for coffee; Strict standards for all Hawaiian coffee growers.

Focuses on the unique culture of the Korean Way of Tea. History of tea in Korea; Preparation and presentation of tea; Status of tea industry.

The fish gill is the most physiologically diversified vertebrate organ, and its vasculature the most intricate. Application of vascular corrosion techniques that couple high-fidelity resins, such as methyl methacrylate, with scanning electron microscopy yields three-dimensional replicas of the microcirculation that have fostered a better appreciate gill perfusion pathways. This is the focus of the present review. Three vascular networks can be identified within the gill filament. The arterioarterial (respiratory) pathway consists of the lamellae and afferent and efferent segments of the branchial and filamental arteries and lamellar arterioles. The body of the filament contains two post-lamellar pathways: the interlamellar and nutrient. The interlamellar system is an extensive ladder-like network of thin-walled, highly distensible vessels that traverses the filament between, and parallel to, the lamellae and continues around the afferent and efferent borders of the filament. Interlamellar vessels are supplied by short, narrow-bore feeder vessels from the medial wall of the efferent filamental artery. A myriad of narrow-bore, tortuous arterioles arise from the basal efferent filamental artery and efferent branchial artery and anastomose to form the nutrient circulation of the arch and filament. In the filament body, nutrient capillaries and interlamellar vessels are often closely associated, and the former may ultimately drain into the latter. Many of the anatomical characteristics of interlamellar vessels are strikingly similar to those of mammalian lymphatic capillaries, with the exception that interlamellar vessels are directly fed by arteriovenous-like anastomoses. It is likely that gill interlamellar and mammalian lymphatics are physiologically, if not embryologically, equivalent. © 2002 Wiley-Liss, Inc.

The fish gill is the primary regulatory interface between internal and external milieu and a variety of neurocrine, endocrine, paracrine, and autocrine signals coordinate and control gill functions. Many of these messengers also affect gill vascular resistance, and they, in turn, may be inactivated (or activated) by branchial vessels. Few studies have critically addressed how flow is distributed within the gill filament, the physiological consequences thereof, or the impact of gill hormone metabolism on gill and systemic homeostasis. In most fish, the entire cardiac output perfuses the arterioarterial pathway, and this network probably accounts for the majority of passive- and stimulus-induced changes in vascular resistance. The in-series arrangement of the extensive gill microcirculation with systemic vessels is also indicative of a high capacity for metabolism of plasma-borne messengers as well as xenobiotics. Adenosine, arginine vasotocin (AVT), and endothelin (ET) are the most potent gill constrictors identified to date, and all decrease lamellar perfusion. Perhaps not surprising, they are also inactivated by gill vessels. Acetylcholine favors perfusion of the alamellar filamental vasculature, although the physiological relevance of acetylcholine-mediated responses remains unclear. Angiotensin, bradykinin, urotensin, natriuretic peptides, prostaglandins, and nitric oxide are vasoactive to varying degrees, but their effects on intrafilamental blood flow are unknown. If form befits function, then the complex vascular anatomy of the gill suggests a level of regulatory sophistication unparalleled in other vertebrate organs. Resolution of these issues will be technically challenging but unquestionably rewarding. © 2002 Wiley-Liss, Inc.

The fish gill is the most physiologically diversified vertebrate organ, and its vasculature the most intricate. Application of vascular corrosion techniques that couple high-fidelity resins, such as methyl methacrylate, with scanning electron microscopy yields three-dimensional replicas of the microcirculation that have fostered a better appreciate gill perfusion pathways. This is the focus of the present review. Three vascular networks can be identified within the gill filament. The arterioarterial (respiratory) pathway consists of the lamellae and afferent and efferent segments of the branchial and filamental arteries and lamellar arterioles. The body of the filament contains two post-lamellar pathways: the interlamellar and nutrient. The interlamellar system is an extensive ladder-like network of thin-walled, highly distensible vessels that traverses the filament between, and parallel to, the lamellae and continues around the afferent and efferent borders of the filament. Interlamellar vessels are supplied by short, narrow-bore feeder vessels from the medial wall of the efferent filamental artery. A myriad of narrow-bore, tortuous arterioles arise from the basal efferent filamental artery and efferent branchial artery and anastomose to form the nutrient circulation of the arch and filament. In the filament body, nutrient capillaries and interlamellar vessels are often closely associated, and the former may ultimately drain into the latter. Many of the anatomical characteristics of interlamellar vessels are strikingly similar to those of mammalian lymphatic capillaries, with the exception that interlamellar vessels are directly fed by arteriovenous-like anastomoses. It is likely that gill interlamellar and mammalian lymphatics are physiologically, if not embryologically, equivalent. © 2002 Wiley-Liss, Inc.

The fish gill is the primary regulatory interface between internal and external milieu and a variety of neurocrine, endocrine, paracrine, and autocrine signals coordinate and control gill functions. Many of these messengers also affect gill vascular resistance, and they, in turn, may be inactivated (or activated) by branchial vessels. Few studies have critically addressed how flow is distributed within the gill filament, the physiological consequences thereof, or the impact of gill hormone metabolism on gill and systemic homeostasis. In most fish, the entire cardiac output perfuses the arterioarterial pathway, and this network probably accounts for the majority of passive- and stimulus-induced changes in vascular resistance. The in-series arrangement of the extensive gill microcirculation with systemic vessels is also indicative of a high capacity for metabolism of plasma-borne messengers as well as xenobiotics. Adenosine, arginine vasotocin (AVT), and endothelin (ET) are the most potent gill constrictors identified to date, and all decrease lamellar perfusion. Perhaps not surprising, they are also inactivated by gill vessels. Acetylcholine favors perfusion of the alamellar filamental vasculature, although the physiological relevance of acetylcholine-mediated responses remains unclear. Angiotensin, bradykinin, urotensin, natriuretic peptides, prostaglandins, and nitric oxide are vasoactive to varying degrees, but their effects on intrafilamental blood flow are unknown. If form befits function, then the complex vascular anatomy of the gill suggests a level of regulatory sophistication unparalleled in other vertebrate organs. Resolution of these issues will be technically challenging but unquestionably rewarding. © 2002 Wiley-Liss, Inc.

Isolated vessels from four elasmobranchs, yellow stingray (Urolophus jamaicensis), clearnose skate (Raja eglanteria), ghost shark (Hydrolagus novaezelandiae), and spiny dogfish (Squalus acanthias), were examined for the presence of spontaneous contractions (SC). SC were observed in otherwise unstimulated dorsal aortas (DA) from stingray and ghost shark, but not in skate DA. Unstimulated ventral aortas (VA) did not exhibit SC. After treatment of VA with a contractile agonist, SC appeared in stingray and skate but not ghost shark or dogfish. SC in stingray VA were subsequently inhibited by either epinephrine (10^–5 M) or indomethacin (10^–4 M). Agonist contraction also elicited strong SC in ductus Cuvier from stingray, but not from ghost shark or dogfish. SC in dogfish hepatic portal veins (HPV) produced a rhythmical oscillation in tension. The frequency of HPV SC was highest (~1 min^–1) in intact veins and lower (~3 min^–1) in vein segments, indicative of a dominant pacemaker in the intact vessel. SC in HPV were depressed during the first 30 min of hypoxia, but there was substantial recovery over an additional 30 min of hypoxia and complete recovery upon return to normoxia. Addition of 80 mM KCl completely inhibited HPV SC and lowered resting tone. These results show that SC are a common feature of elasmobranch vessels and there appears to be a correlation between swimming behavior and the propensity for SC. KCl inhibition of SC and tonus in HPV is highly unusual for vascular smooth muscle. J. Exp. Zool. 286:606–614, 2000. © 2000 Wiley-Liss, Inc.

Arginine vasotocin (AVT) is present in the neurohypophysis of all nonmammalian vertebrates and it appears to be the antecedent of the neurohypophysial nonapeptide hormones. Relatively little is known about AVT receptors in lower vertebrates, especially fish, and the present study was designed to examine AVT receptor interactions in trout vascular and nonvascular smooth musclein vitro.AVT produced dose-dependent contraction of isolated rings from celiacomesenteric, coronary, and efferent branchial arteries, ventral aorta, anterior cardinal vein, and strips of ductus Cuvier. The greatest efficacy (magnitude of contraction per unit tissue weight) and sensitivity (effective concentration for half-maximal response, EC50) to AVT was found in the efferent bronchial artery (EBA) and its receptors were characterized further. Other neurohypophysial peptides, including arginine vasopressin (AVP), lysine vasopressin (LVP), isotocin (IST), and oxytocin (OXY), contracted EBA with an efficacy order of (most to least) AVT = AVP = OXY > LVP > IST and a sensitivity order of AVT > OXY ≥ AVP > IST > LVP. Neither Desmopressin, an AVP V2-receptor agonist, nor the AVP ring fragment, AVP4–9, contracted EBA nor did they inhibit AVT contraction. Pretreatment of EBA rings with the selective AVP V1-receptor antagonists (deamino-Pen1, O-Me-Tyr2, Arg8-vasopressin and deamino-Pen1, Val4, Arg8-vasopressin), the selective V2-receptor antagonist (adamantaneacetyl1, O-Et-d-Tyr0, Val4, aminobutyryl6, Arg8,9-vasopressin), or the combined V1-oxytocin receptor antagonist (d(CH2)5[Tyr(Me)2, Orn8-AVT]) competitively inhibited AVT contractions without affecting AVT efficacy. Receptor affinity constants (pA2) determined by Schild analysis were in the range of 6.8–7.3, with slightly higher constants for the AVP V1-/oxytocin receptor antagonists than for the selective V2-receptor antagonist. Endothelium removal had no effect on EBA sensitivity to AVT. EBA rings were an order of magnitude more sensitive to AVT than nonvascular gastrointestinal and urinary bladder smooth muscle rings or strips. However, AVT (10−7M) was as efficacious as acetylcholine (10−5M) in gastrointestinal, gallbladder, and urinary bladder smooth muscle. It is concluded that trout EBA possess an AVT smooth muscle receptor that shares a similar pharmacological profile with the mammalian vascular AVP V1a-receptor and the OXY-receptor, but it is distinct from the previously reported gill epithelial cell receptor.

The effects of arginine vasotocin (AVT) were examined in isolated gar arteries (afferent branchial, ABA; conus arteriosus, CA; ventral aorta, VA) and veins (hepatic, HV; intestinal; ovarian). AVT (10−11–10−7M) had no effect in CA, produced contraction in ABA and VA and stimulated relaxation in veins. In precontracted HV, AVT relaxation was dose-dependent, long-lived (>30 min) and reduced total tension by 49.0 ± 10.7%. EC50s for AVT, arginine vasopressin, oxytocin, desmopressin, and isotocin in gar HV were 1.4 ± 0.3, 3.6 ± 0.2, 5.3 ± 1.7, 11.0 ± 6.5, and 19.0 ± 0.4 nM,respectively. AVT was more potent compared with isotocin. Strength of relaxation (percentage decrease in total tension) of AVT and structural analogs was similar (range=32.5 to 55%). Endothelium removal did not alter percentage relaxation or sensitivity to AVT in HV. AVT relaxation was not inhibited by nitric oxide synthase inhibitors or propranolol or reversed by addition of methylene blue but it was significantly enhanced by indomethacin (10−5M). Arginine vasopressin-receptor antagonists (V1- or V2-type selectivity; 10−6M) were equally effective inhibitors, each blocked 99% of AVT relaxation. Forskolin (10−6M) and papaverine (10−4M) relaxed precontracted gar arteries and veins. The adenylyl cyclase inhibitors SQ 22536 and MDL 12,330A (10−5M) produced transient contraction and stable relaxation, respectively, but did not inhibit AVT-induced relaxation in HV. Atrial natriuretic peptide (3×10−8M) and sodium nitroprusside (10−4M) had no effect in precontracted HV. AVT acts directly on gar venous smooth muscle cells via a nonclassical AVP receptor, possibly by increasing [cAMP]. AVT is a potent vasoconstrictor in vertebrate vasculature but produces a novel relaxation in gar veins.

Low accuracy of soil spectral classes within areas with thin surficial mantles is often due to confusion caused by differences in the underlying parent materials in large imageries. This study was conducted to determine whether satellite digital data could be used to predict underlying soil parent material at specific locations in a glaciated landscape with a thin loess mantle. Soils were sampled on two regular grids, each covering an area of 3,108 ha, in Ford County, Illinois. The soils developed in thin loess over both loamy and clayey glacial till, outwash, and lacustrine sediments of the Wisconsinan glaciation. Satellite spectral data obtained over parent materials underlying a thin loess mantle and from an undulating site were statistically analyzed by multipleregression procedure to develop a model (linear equation) to predict underlying soil parent material with a thin loess mantle. Correlations between underlying parent material and the red band, green band, and brightness index were significant (0.212, 0.267, and 0.176, respectively) at the 0.01 level. The absence of loess mantle at some of the undulating reference sites due to erosion and the presence of a new parent material underlying the loess mantle at the test site contributed to the differences between predicted and observed underlying parent materials. For these reasons correlations presented only accounted for a small amount of the variation. Model-predicted underlying parent materials of the nearly level test area showed a significant correlation of 0.148 with actual values. The possibility for reasonable subdivision of an image suggests a potential for improving spectral soil maps by separation of large survey areas with thin loess mantles by underlying parent materials prior to computer classification.

We investigated two areas of contrasting spatial variability in east-central Illinois using grid sampling to determine the composition of soil map units and the variability of significant soil properties within map units. We also evaluated the effectiveness of the modern soil survey legend and maps in addressing the soil variability in the two different landscapes. The surface characteristics of the sample sites showed extremely high variability, especially in slope and aspect with CVs of 93.5 and 83.6, respectively. The depth of the A horizon showed high variability with CV of 35 for both areas. The depth to reducing conditions was highly variable with a CV of 34.6, while the depth to discontinuity was 48.4. Characteristically the degree of color variability increased in the order, hue, value, and chroma, regardless of where in the profile it occurred. The A horizon showed very high variability in sand content with a CV of 74.4, but silt content and clay content both showed moderate variability with CVs of 22.9 and 23.6, respectively. Organic C content showed moderate variability with CV of 15 and was more variable in the highly undulating landscape, probably due to redistribution by erosion. Soil reaction in the B horizon showed a low degree of variation with CV of 9.5. Although the variability of each soil property within the eight map units measured by coefficient of nondetermination showed less variance than the total variance present in both sample areas, most of the variation of soil properties was still left within map units. Tolerance limits of 75 set for the various map units indicate that some of the map units contained less variation of soil properties than others. This approach should help in refining the cartographical separations by identifying potential units that need reduction in variation of selected properties. Based on evaluation of soil property variability, we found that although the existing soil survey legend and maps are good, they could be improved substantially by considering the within-map unit variability of significant soil properties. We recommend that in future soil surveys, an initial soil property variability study be conducted using grid sampling to aid in a comprehensive development of the soil survey legend which will help reduce the within-map unit variation.

It has been suggested that a decline in curiosity is one characteristic manifested by depressed individuals. However, no experimental research has examined the relationship between depression and curiosity. In this study, the Velten mood induction procedure was utilized to examine the relationship between curiosity and affect, and to investigate the effects of induced mood on ratings of surprise, perceived value of information, and desire for additional knowledge. A total of 39 female and 21 male undergraduates were randomly assigned to one of three mood conditions: a depression mood condition, an elation mood condition, or a neutral mood condition. Results indicated that subjects made temporarily depressed reported significantly less state curiosity, perceived value of information, and desire for additional knowledge than elated or neutral subjects. Implications of these findings are discussed.

The secondary circulation is an arterial‐capillary‐venous system derived from, and in parallel with, the general (primary) circulation of fish. Narrow‐bore (2–20 μm diameter × 200–300 μm length), tortuous arterioarterial (interarterial) anastomoses arise from the efferent filamental and efferent branchial arteries of the gill, dorsal aorta, and segmental arteries and condense to form progressively larger secondary arteries. Secondary capillaries have been identified in gills, skin, fins, peritoneal lining, and oral mucosa of bony fish and in gills of many nonteleostean species. Their endothelium is thin‐walled with overlapping cell junctions reminiscent of mammalian lymphatic capillaries. Branchial secondary veins drain into primary veins of the head, systemic secondary veins primarily drain into the caudal heart, or into large cutaneous veins, and from there blood enters the primary venous system. Preliminary studies indicate that the secondary circulation is a large‐volume (48.4 ml·kg−1, 1.5 times greater than the primary system), low‐flow (0.3% of cardiac output) network. Microvillous endothelial cells in the primary artery guard the entrance to secondary vessels and restrict access of red blood cells. Close proximity of secondary capillaries to exposed epithelia is suggestive of an ion, volume or immunoregulatory function, although low flow through the secondary system may limit the efficiency of some of these processes. Recent studies indicate that fish lack a true lymphatic system and analogies between the secondary system and lymphatics have been noted. It remains to be determined whether the secondary system is the antecedent of a lymphatic system or a coincidentally similar structure. © 1996 Wiley‐Liss, Inc.

In a greenhouse experiment, we evaluated the effects of scrubber sludge on the aggregation and the porosity in various combinations of dredged sediments and topsoil in the presence of sudangrass roots. As expected, the water-stable aggregates increase with increasing percentage of topsoil. For all combinations, scrubber sludge decreased aggregation. The topsoil had a total porosity similar to the sediments at the completion of the study in the absence of scrubber sludge. The total porosity increased with additional quantities of scrubber sludge for all combinations of topsoil and sediments. Transmission (>50 μm), water storage (50 to 0.5 μm), and residual (0.5 μm) pore volumes differed substantially between the sediments and topsoil, as well as with scrubber sludge treatments. The sediments had a higher water retention difference than the topsoil. The presence of scrubber sludge had little effect on topsoil, but reduced the water storage volumes for the sediments. With scrubber sludge addition, the residual pore volumes remained high for topsoil, but decreased substantially for sediments. For all combinations of topsoil and sediments, scrubber sludge dramatically increased transmission porosity. This increase in transmission pores within the sediments with scrubber sludge additions resulted in a higher rate of saturated flow of water than for the sediments without scrubber sludge. The pore-size distributions were estimated by water-release methods and verified by directly measuring soil pore-size distributions by Hg-intrusion porosimetry.

Factor analyses were conducted of several commonly used questionnaire measures of curiosity in adults. A General Curiosity factor emerged in both total scale and subscale factorings. This factor included the Melbourne State and Trait Personality Questionnaires, the Academic Curiosity Scale, the Ontario Test of Intrinsic Motivation Specific Curiosity subscales, and Spielberger's State and Trait Curiosity Inventories. Rather than measuring curiosity, the Proverbs Test appeared to reflect venturesomeness, and the Diversive Curiosity Scale and Sensation Seeking Scale loaded on an Experience Seeking factor. Additional findings are discussed.

Hormone titers are affected by interplay between secretion and inactivation processes. While secretion is a focal process, inactivation mechanisms are often complex and poorly understood. In the present study, inactivation of cardiovascular regulatory hormones was examined from a physiological perspective by analyzing the half-time (t½) for recovery of dorsal and ventral aortic and central venous pressure, cardiac output, heart rate, and systemic and branchial vascular resistance following infusion or injection of hormones into conscious rainbow trout, Oncorhynchus mykiss. When possible, these were compared to recovery t½ of isolated vessel rings in vitro. The t½ for epinephrine or norepinephrine recovery in vivo was 3–4 min, approximately twice as long as recovery t½ for isolated celiacomesenteric and epibranchial artery rings in vitro. Thus, the rate-limiting step in vascular relaxation is the concentration of circulating catecholamine concentrations, and not metabolic or mechanical events within the vascular wall. The in vivo recovery t½ following angiotensin II (ANG II) infusion was 6–7 min, nearly twice that of catecholamines, but also greater than the t½ following bolus ANG II injection, inhibition of angiotensin converting enzyme with captopril or injection of trout bradykinin. Arginine vasotocin (AVT) recovery t½ in vivo, was considerably longer (20–30 min) than either catecholamine or ANG II t½ and longer than AVT recovery t½ of isolated vessels in vitro (5–6 min). The inactivation kinetics of catecholamines are consistent with circulatory convection-limited processes and do not appear to be limited by either tissue uptake or enzymatic degradation. This is probably the fastest type of ‘on-off’ endocrine regulation in fish. Inactivation of ANG II and bradykinin are also convection limited, but ANG II metabolism may become saturated with high doses of exogenous ANG II. AVT inactivation is not convection limited and may compensate for a quantitatively lower capacity of the pituitary for peptide secretion, or less emphasis on AVT as an on/off effector of vascular resistance. J. Exp. Zool. 279:254–264, 1997. © 1997 Wiley-Liss, Inc.

Atrial natriuretic peptides (ANP) are potent effectors of volume homeostasis in mammals, but their effects on fluid compartments in teleost fish are unknown. In the present study, whole-body blood volume (BV: ⁵¹Cr-red cells), and extracellular fluid volume (ECFV; ⁵⁸Co-EDTA space), and ⁵¹Cr-red cell and ⁵⁸Co-EDTA space in 31 tissues was measured in unanesthetized trout infused for 8 h with saline (1.2 mlh^-1kg^-1) or with rat atrial natriuretic peptide (Ile-26; ANP) at a rate of (300 ngh^–1kg^-1 at 1.2 mlh^-1kg^-1). Urine flow was also measure and ⁵⁸Co-EDTA clearance provided an index of glomerular filtration (GFR). ANP infusion significantly decreased BV from 29.0±1.2 (n=22; saline) to 22.9±1.0 mlkg^-1 (P≤0.01, n=22; ANP) and ECFV from 242±17 (n=14; saline) to 170±6 mlkg^-1 (P≤0.001, n=14; ANP); therefore, the majority of the fluid lost is from the interstitial compartment. ANP increased red cell space in gill, pectoral fin, brain, eye, and bulbus, presumably through local vascular effects, and decreased it in caecum. ANP decreased ECFV in anterior kidney, liver, gill, anterior intestine, posterior intestine, caecum, swimbladder, gall bladder, operculum, skull, pelvic fin and dorsal skeletal muscle. ECFV was also slightly reduced by ANP infusion in all other tissues, although not significantly, suggesting a general extracellular dehydration. Urine excretion and GFR increased (P≤0.01) from 2.9±0.4 and 5.7±0.1mlh^-1kg^-1 in saline infused trout (n=11, 9, respectively) to 6.3±0.8 and 12.7±2.3 mlh^-1k^-1 in ANP infused trout (n=15, 12, respectively). These data show that ANP is hypovolemic in trout and that an increased GFR is the principal mechanism through which urine output is increased. Increased urine formation, however, can only account for 40% of the decrease in extracellular fluid volume. Translocation of extracellular fluid into other compartments, including intracellular compartments must be considered. J. Exp. Zool. 278:215–220, 1997. © 1997 Wiley-Liss, Inc.

Procedures in Illinois to establish new soil series and productivity indexes for the assessment of reclaimed farmland disturbed by surface mining and reclaimed under various statutes are discussed. The interim assessment approach maintains the productivity index (PI) of a tract of land at either 90 or 100% of the PI of the original soils during surface mining and reclamation. The recommended long-term approach will establish a new tract PI based on the actual soil series present after disturbance by surface mining and all reclamation has been applied, including productivity restoring treatments. Before the recommended long-term approach can be implemented, the following tasks will need to be completed: (i) additional soil series on surface mined soils with or without reclamation and/or compaction alleviating treatments, (ii) a soil scientist should be assigned to resurvey a reclaimed area after all reclamation and productivity restoring treatments have been completed and final bond release has occurred, and (iii) crop yields and PI' are assigned after an evaluation of the soil properties and plot yield data.

Fly ash from coal burning often takes the form of magnetic spherules, making it easy to separate and identify. Illinois soils near to and remote from known sources of fly ash were studied to evaluate ash incidence and accumulation of ash‐bearing sediments in the profile. Soils from both types of areas contained magnetic fly‐ash spherules. Concentrations >75% occurred in the magnetic fraction of the surface horizon (mostly in the top 12.5 cm) of a soil on an uncultivated, stable ridgetop near Springfield, IL. On the nearby Sangamon River floodplain, fly ash occurred in large numbers to the 25‐cm depth, and in lesser numbers to 45 cm, the top of a buried, organic‐C‐rich layer. This buried layer may represent the surface in the 1850s, when railroads and perhaps also industrial boilers were introduced. In depositional horizons of soils from remote sites, fly ash occurred at levels of <1%; it probably came from steam locomotives and, perhaps, steam‐powered farm machinery. From the 1850s to the late 1920s, railroads in Illinois increased to about 16 000 km of track; consequently, fly ash is ubiquitous in surface soils and is easily assayed. Steam‐powered farm machinery (although not always fueled by coal) was common from 1880 until about 1920. At depositional sites, the buried A horizon contained fly ash, but subjacent horizons did not. This pattern indicates that fly ash occurrence is useful in distinguishing the presettlement surface, thereby making possible the determination of rates of sedimentation at a particular site.

The purpose of this study was to establish the relationship between soil taxonomic description, landscape form and position, and erosion in northwest Illinois. The study area consists of a first‐order drainage basin about 10 ha in size. The hillslopes have mean gradients of 6 to 10% with overland flow the primary contributor to erosion. A detailed geomorphic map of the watershed was constructed on a 1‐m topographic survey base map. Map units were delineated based on slope shape, gradient, and USDA erosion class. Erosion classes were determined for the transect pedons by comparison with two uneroded and uncultivated pedons in area cemeteries with similar slope gradient, slope shape, slope length, and landscape positions. The A horizon thickness and organic C content decreased and clay content increased as a consequence of cultivation and erosion. Transect data for all hillslope geomorphic units showed the erosion classes near the shoulder to be either slightly or moderately eroded. The lower backslopes and upper footslopes, just above the sediment basin, were either severely or very severely eroded, suggesting slope length to be the dominant factor affecting erosion. The geomorphic units with concave across‐slope shapes were found to be less eroded than those with convex across‐slope shapes. All cultivated pedons failed to meet the criteria for Mollisols, which was the taxonomic placement of the uncultivated pedons. Erosion phase, landscape segment, slope shape, slope gradient, and slope length affected the taxonomic placement of the cultivated hill‐slope soils when compared with uncultivated sites.

Incubation of plasma from the steelhead trout, Oncorhynchus mykisswith porcine pancreatic glandular kallikrein generated bradykinin‐like immunoreactivity. The primary structure of the immunoreactive peptide was established as: Lys‐Arg‐Pro‐Pro‐Gly‐Trp‐Ser‐Pro‐Leu‐Arg. This sequence shows two amino acid substitutions (Phe6→Trp and Phe9→Leu) compared with mammalian lysyl‐bradykinin (kallidin). Bolus intra‐arterial injection of the purified peptide produced a strong and sustained vasopressor response in the unanaesthetized trout. The data demonstrate that the kallikrein—kinin system predates the appearance of tetrapods and suggest a role for this system in cardiovascular regulation in fish.

Scanning electron micrographs of gill tissue from rainbow trout fixed with 50% glutaraldehyde revealed the presence of microridges on surfaces of epithelial cells of the secondary lamellae. These microridges vary in length from 1 to 7 µ, with a mean height of 0.75 µ. Calculations show that they increase the total lamellar epithelial surface area approximately 2.5 fold. Mucus secreting cells are present on the body of the filament and on secondary lamellae. Chloride cells are located primarily in the interlamellae filamental epithelium and on the basal area of lamellae. Extensions of the chloride cell epithelium are microvillous in nature and their height is only slightly greater than that of the microridges of typical lamellar epithelial cells. A reduction in number or complete absence of microvilli on chloride cells appeared to be related to degenerative changes in these cells observed in transmission electron micrographs. Non secretory interlamellae filamental epithelial cells have microridges of very attenuated lengths.

1.The relative functional surface area of isolated-perfused gills was evaluated by measuring the influx of14C-urea, a passively diffusing molecule.2.The catecholamines, norepinephrine and epinephrine, increase functional gill surface area and decrease overall branchial vascular resistance.3.Surface area and resistance effects of adrenergic agonists and blocking agents demonstrated the presence of both a and ß adrenergic receptors in rainbow trout gills.4.Stimulation of a adrenergic receptors increased both functional surface area and branchial vascular resistance, while ß adrenergic receptor stimulation increased functional surface area but decreased branchial vascular resistance.5.Acetylcholine decreased functional gill surface area and increased overall branchial vascular resistance.6.The data presented strongly indicate that the functional surface area of rainbow trout gills can be regulated by changing perfusion pathway with adjustments in the relative vascular resistance across the different pathways.

The renal and in vitro vascular effects of atrial natriuretic peptides have been examined in seveal species of fish. However, comparatively few investigations have described the effects of these peptides on the cardiovascular system in vivo. In the present experiments the dorsal aorta and urinary bladder were cannulated and the effects of atrial natriuretic peptides from rat and eel were monitored in conscious trout during bolus injection or continuous atrial natriuretic peptide infusion. The results show that the initial pressor effect of atrial natriuretic peptides is independent of environmental salinity adaptation (fresh or seawater) and the chemical form of atrial natriuretic peptide injected, but it is affected by the rate of atrial natriuretic peptide administration. This pressor response, and the accompanying diuresis, are mediated through a-adrenergic activation. Continuous infusion of either rat or eel atrial natriuretic peptide produces a steady fall in mean arterial blood pressure, which is temporally preceded by an increase in heart rate and a decrease in pulse pressure. Diuresis induced by atrial natriuretic peptides is only partially sustained during continuous infusion. Propranolol partially blocks the increase induced in heart rate by atrial natriuretic peptides, but does not affect either pulse pressure or mean arterial pressure. Propranolol significantly increases urine flow in saline-infused animals but has no apparent effect on animals subjected to infusions of atrial natriuretic peptides. These results indicate that there are multiple foci for the action of atrial natriuretic peptides in trout and that in many instances the effects of atrial natriuretic peptides are mediated through secondary effector systems.

The effect of atrial natriuretic peptide (ANP) was examined on longitudinal and circular smooth muscle of esophagus, stomach, anterior and posterior intestine, and longitudinal muscle of the pyloric ceca from the rainbow trout (Oncorhynchus mykiss). ANP had the greatest effect in longitudinal stomach (LS) where it reduced spontaneous rhythmical contractions and baseline tension in otherwise unstimulated strips. ANP relaxed LS precontracted with 10−6M acetylcholine (ACh) in a dose-dependent manner (pD2= 8.39 ± 0.07; N= 8). Pretreatment of LS with 10−6M tetrodotoxin (TTX) did not affect the ability of ANP to relax ACh contractions (pD2before TTX = 8.48 ± 0.09 versus 8.47 ± 0.06 after TTX; N= 7). ANP produced modest inhibitory effects in other longitudinal gastrointestinal (GI) smooth muscle, decreased the rate of, but did not inhibit, rhythmical activity in anterior intestine, and slightly increased tension of rhythmical contractions in esophageal and anterior intestine. ANP was virtually ineffective on all circular smooth muscle. It is concluded that, in addition to the well known direct effects of this peptide on GI absorption, ANP may affect GI function through regulation of motility.

The morphology of the gills of a primitive air breather (Amia calva) was examined by light microscopy of semithin sections of gill filaments, and gill perfusion pathways were identified by scanning-electron microscopic analysis of corrosion replicas prepared by intravascular injection of methyl methacrylate. The arrangement of gill filaments and respiratory lamellae is similar to that of teleosts with the exception of an interfilamental support bar that is fused to the outer margins of lamellae on adjacent filaments. The prebranchial vasculature is also similar to that of teleosts, whereas the postbranchial circulation of arches III and IV is modified to permit selective perfusion of the air bladder. Gill filaments contain three distinct vascular systems: (1) the respiratory circulation which receives the entire cardiac output and perfuses the secondary lamellae; (2) a nutrient system that arises from the postlamellar circulation and perfuses filamental tissues; (3) a network of unknown function consisting of subepithelial sinusoids surrounding afferent and efferent margins of the filament and traversing the filament beneath the interlamellar epithelium. Prelamellar arteriovenous anastomoses (AVAs) are rare, postlamellar AVAs are common especially at the base of the filament where they form a dense network of small tortuous vessels before coalescing into a large filamental nutrient artery. Unlike in most teleosts, the outer vascular margins of the lamellae are embedded in the interfilamental support bar and become the sole vasculature of this tissue. Arterial-arterial lamellar bypass vessels were not observed. Previously observed decreases in oxygen transfer across the gills during air breathing can be explained only by redistribution of blood flow between or within the respiratory lamellae.

The Illinois Agricultural Experiment Station has been a major contributor to the Soil Survey of Illinois since 1902. Initial activities included mapping soil types by county, conducting soils investigation and genesis studies, collaborating in the development of soil science, promoting the use of soil survey information, and developing soil productivity indexes. Later, the Experiment Station provided laboratory soil characterization data for county soil surveys and computerized all of the laboratory soil property data for Illinois pedons including many long-term studies relating soil properties to soil parent material. Mineralogists established that most soil clay in Illinois was crystalline with montmorillonite predominant in Peoria loess and illite in Wisconsinan glacial till. Mineralogists used the presence of significantly more biogenetic opal to identify soils formed under long periods of grass rather than trees. In recent years the Illinois Agricultural Experiment Station: conducted research on reclamation of agricultural soils disturbed by surface mining, quantified soil loss from erosion, studied the effects of erosion on soil properties and crop yields, evaluated methods to maintain or restore productivity on previously eroded soils, and studied the effects of accelerated erosion on the taxonomic placement of Illinois soils. Most of the research was conducted to address classification and interpretational needs of the soil survey.

The biological effects of oxidants, especially reactive oxygen species (ROS), include signaling functions (oxidative eustress), initiation of measures to reduce elevated ROS (oxidative stress), and a cascade of pathophysiological events that accompany excessive ROS (oxidative distress). Although these effects have long been studied in animal models with perturbed ROS, their actions under physiological conditions are less clear. I propose that some of the apparent uncertainty may be due to confusion of ROS with endogenously generated reactive sulfur species (RSS). ROS and RSS are chemically similar, but RSS are more reactive and versatile, and can be stored and reused. Both ROS and RSS signal via oxidation reactions with protein cysteine sulfur and they produce identical effector responses, but RSS appear to be more effective. RSS in the form of persulfidated cysteines (Cys-S-S) are produced endogenously and co-translationally introduced into proteins, and there is increasing evidence that many cellular proteins are persulfidated. A number of practical factors have contributed to confusion between ROS and RSS, and these are discussed herein. Furthermore, essentially all endogenous antioxidant enzymes appeared shortly after life began, some 3.8 billion years ago, when RSS metabolism dominated evolution. This was long before the rise in ROS, 600 million years ago, and I propose that these same enzymes, with only minor modifications, still effectively metabolize RSS in extant organisms. I am not suggesting that all ROS are RSS; however, I believe that the relative importance of ROS and RSS in biological systems needs further consideration.