Voluntary sustainability standards could significantly reduce detrimental impacts of global agriculture.

Voluntary sustainability standards (VSS) are stakeholder-derived principles with measurable and enforceable criteria to promote sustainable production outcomes. While institutional commitments to use VSS to meet sustainable procurement policies have grown rapidly over the past decade, we still have relatively little understanding of the (i) direct environmental benefits of large-scale VSS adoption; (ii) potential perverse indirect impacts of adoption; and (iii) implementation pathways. Here, we illustrate and address these knowledge gaps using an ecosystem service modeling and scenario analysis of Bonsucro, the leading VSS for sugarcane. We find that global compliance with the Bonsucro environmental standards would reduce current sugarcane production area (-24%), net tonnage (-11%), irrigation water use (-65%), nutrient loading (-34%), and greenhouse gas emissions from cultivation (-51%). Under a scenario of doubled global sugarcane production, Bonsucro adoption would further limit water use and greenhouse gas emissions by preventing sugarcane expansion into water-stressed and high-carbon stock ecosystems. This outcome was achieved via expansion largely on existing agricultural lands. However, displacement of other crops could drive detrimental impacts from indirect land use. We find that over half of the potential direct environmental benefits of Bonsucro standards under the doubling scenario could be achieved by targeting adoption in just 10% of global sugarcane production areas. However, designing policy that generates the most environmentally beneficial Bonsucro adoption pathway requires a better understanding of the economic and social costs of VSS adoption. Finally, we suggest research directions to advance sustainable consumption and production.

Temperatures of desert plants: another perspective on the adaptability of leaf size.

Surface temperatures of perennial plants in the Sonoran Desert of California ranged from 20 degrees C above air temperature to over 18 degrees C below air temperature during rapid growth periods following rain. Desert cactus with large photosynthetic stem surfaces had the highest temperatures and lowest transpiration rates. Perennial plants with relatively small leaves had moderate transpiration rates and leaf temperatures close to air temperature. Desert perennials with relatively large leaves had leaf temperatures well below air temperature along with the greatest accompanying transpiration rates of over 20 micrograms per square centimeter per second, but also had correspondingly low temperatures for maximum photosynthesis. The low leaf temperatures measured for these large-leafed species are an exception to the more common pattern for desert plants whereby a smaller leaf size prevents overheating and leads to reductions in transpiration and increased water-use efficiency. The contribution of a larger leaf size to a lower leaf temperature, and thus higher rate of photosynthesis for these large-leafed species, may represent an adaptive pattern previously unrecognized for desert plants.

A renal countercurrent system in marine elasmobranch fish: a computer-assisted reconstruction.

Computer-aided techniques were used to reconstruct the complex renal tubular system in the dorsal kidney region of a marine elasmobranch fish, the little skate (Raja erinacea), from a series of light micrographs of serial sections. It was established that five individual segments of one nephron, consisting of two loops and a distal tubule, are arranged in parallel within an elongated closed tissue sac. Capillaries, which form a network around these nephron segments, enter and exit this sac at the same end. This anatomical arrangement suggests that a complex renal countercurrent multiplier system may be important in fluid regulation in these fish.

A national survey amongst UK otolaryngologists regarding the treatment of Ménière's disease.

Since Dr Prosper Ménière described the vertiginous syndrome that now bears his name, a large variety of medical and surgical treatments have been introduced. To determine the way in which this condition is currently managed in the United Kingdom, a postal survey amongst consultant otolaryngologists was carried out. It revealed that 52 per cent were actively involved in the treatment of patients with Ménières disease using a wide range of medical and surgical therapies that have little or no evidence base. The survey found that 94 per cent of surgeons prescribe betahistine, 63 per cent diuretics and 71 per cent advise salt restriction to their patients, while 52 per cent of surgeons continue to recommend saccus decompression and 50 per cent are still inserting a grommet. However, two thirds of respondents now advocate the use of gentamicin therapy despite it only being introduced to this country just over 10 years ago. The results of this study and their relevance to the recommended present day management of Meniere's disease are discussed.

Effect of caffeine on ibuprofen analgesia in postoperative oral surgery pain.

Recent studies have demonstrated that caffeine acts as an analgesic adjuvant when combined with acetaminophen, aspirin, or their mixture. Our objective was to determine whether similar enhancement of analgesia could be demonstrated when caffeine is combined with ibuprofen. On a double-blind basis, a single oral dose of ibuprofen (50, 100, or 200 mg), a combination of ibuprofen, 100 mg, with caffeine, 100 mg, a combination of ibuprofen, 200 mg, with caffeine, 100 mg, or placebo was randomly assigned to 298 outpatients with postoperative pain after the surgical removal of impacted third molars. With a self-rating record, subjects rated their pain and its relief hourly for 8 hours. All active treatments were significantly superior to placebo, and the caffeine effect was significant for every measure of analgesia. Relative potency estimates indicated that the combination was 2.4 to 2.8 times as potent as ibuprofen alone. The combination also had a more rapid onset and longer duration of analgesic action. The analgesic adjuvancy of caffeine clearly extends to combinations with nonsteroidal anti-inflammatory drugs other than acetaminophen or aspirin.

Analgesic efficacy of bromfenac, ibuprofen, and aspirin in postoperative oral surgery pain.

We recently demonstrated that 25 mg of bromfenac, a new nonsteroidal anti-inflammatory analgesic, is at least as effective as 400 mg of ibuprofen in relieving postoperative oral surgery pain. Our objective in this study was to determine whether higher doses were significantly more effective. Two hundred eighty (280) outpatients with postoperative pain after the surgical removal of impacted third molars were randomly assigned, on a double-blind basis, a single oral dose of 10, 25, 50, or 100 mg bromfenac; 650 mg aspirin; 400 mg ibuprofen; or placebo. Subjects rated their pain and its relief for 8 hours. All active treatments were significantly superior to placebo, and bromfenac and ibuprofen were significantly superior to aspirin. The slope of the dose-response curve of bromfenac was significant. The 100 mg bromfenac dose was significantly more effective than the 400 mg ibuprofen dose and had a significantly longer duration of analgesic action.

Rat medulla oblongata. IV. Topographical distribution of catecholaminergic neurons with quantitative three-dimensional computer reconstruction.

We examined serial 40 micron vibratome, immunoperoxidase-stained sections of the medulla with tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DBH), and phenylethanolamine N-methyltransferase (PNMT) antisera followed by Nissl staining to locate catecholaminergic neurons in cytoarchitectonic regions followed by a three-dimensional (3D) computer reconstruction of these cell groups to determine their spatial organization. Overlay drawings of low and high power photomicrographs showing cell bodies and nuclear boundaries were entered into a digital computer storage system. Every section in the series was plotted to yield an accurate representation of regional densities of cells and location of nuclei, as revealed by two-dimensional plots of individual sections as well as three-dimensional plots of groups of sections. Data files were scanned in a number of ways to obtain total cell counts of TH-, DBH-, and PNMT-immunoreactive cells within a designated area or cell counts of only one type of immunoreactive cell. This combination of data manipulation produced the following results: (1) A1 group is a homogeneous population of noradrenergic neurons at levels caudal to the obex, and at the obex it is mixed with adrenergic cells. The dimensions of the A1 cell group are 1.3 X 2.7 mm, extending from -2.5 to +0.2. Part of this cell group lies in the lateral reticular nucleus. (2) A2 group is not purely noradrenergic as previously suspected. It is a very mixed cell group containing mainly dopaminergic neurons in the area postrema (periventricular region) and the dorsal motor nucleus of the vagus, mainly noradrenergic neurons in the medial subnucleus of the nucleus of the tractus solitarius (nTS), mainly adrenergic neurons in the dorsal strip and dorsal subnucleus of the nucleus of the tractus solitarius, and a mixture of all three catecholaminergic neurons in the other subnuclei of the nTS. The dimensions of this group are 0.4 X 3 mm extending from -2.7 to +0.3. (3) C1 group is a homogeneous population of adrenaline cells extending from +1 to +2.5 with dimensions of 1.5 X 1.5 mm and consisting of scattered neurons some of which occupy the gigantocellular reticular nucleus. (4) C2 group is a homogeneous population of adrenaline neurons extending from +1 to +3 with dimensions of 2.5 X 3 mm. Accurate visual imaging and quantitation of the spatial organization of medullary catecholaminergic neurons within the classical anatomical framework of cytoarchitecture provides an enhanced comprehension of the organization of this region of the central nervous system.

Computer-assisted three-dimensional reconstructions of [14C]-2-deoxy-D-glucose metabolism in cat lumbosacral spinal cord following cutaneous stimulation of the hindfoot.

We report on computer-assisted three-dimensional reconstruction of spinal cord activity associated with stimulation of the plantar cushion (PC) as revealed by [14C]-2-deoxy-D-glucose (2-DG) serial autoradiographs. Moderate PC stimulation in cats elicits a reflex phasic plantar flexion of the toes. Four cats were chronically spinalized at about T6 under barbiturate anesthesia. Four to 11 days later, the cats were injected (i.v.) with 2-DG (100 microCi/kg) and the PC was electrically stimulated with needle electrodes at 2-5 times threshold for eliciting a reflex. Following stimulation, the spinal cord was processed for autoradiography. Subsequently, autoradiographs, representing approximately 8-18 mm from spinal segments L6-S1, were digitized for computer analysis and 3-D reconstruction. Several strategies of analysis were employed: 1) Three-dimensional volume images were color-coded to represent different levels of functional activity. 2) On the reconstructed volumes, "virtual" sections were made in the horizontal, sagittal, and transverse planes to view regions of 2-DG activity. 3) In addition, we were able to sample different regions within the grey and white matter semi-quantitatively (i.e., pixel intensity) from section to section to reveal differences between ipsi- and contralateral activity, as well as possible variation between sections. These analyses revealed 2-DG activity associated with moderate PC stimulation, not only in the ipsilateral dorsal horn as we had previously demonstrated, but also in both the ipsilateral and contralateral ventral horns, as well as in the intermediate grey matter. The use of novel computer analysis techniques--combined with an unanesthetized preparation--enabled us to demonstrate that the increased metabolic activity in the lumbosacral spinal cord associated with PC stimulation was much more extensive than had heretofore been observed.

Leptin and maternal growth during adolescent pregnancy.

BACKGROUND: Maternal growth on the basis of knee height occurs in nearly 50% of pregnant teenagers and is associated with greater gestational weight gain and accrual of subcutaneous fat in the mother but lower fetal growth compared with nongrowing teenagers and mature pregnant women. OBJECTIVE: The objective of this study was to determine whether leptin is a biomarker for continued maternal growth. DESIGN: Leptin concentrations were measured in 162 growing and nongrowing teenage gravidas (aged 5-fold, fetal growth restriction increased >6-fold, and infant birth weight decreased by approximately 200 g. Gravidas who developed pregnancy-induced hypertension showed a different pattern-higher leptin concentrations at entry and week 28, no difference in the leptin surge, and no postpartum difference in leptin concentration. CONCLUSION: A leptin surge by week 28 appears to mark reduced mobilization of maternal fat stores that is associated with maternal growth on the basis of knee height during adolescent pregnancy.

Hemorrhagic diathesis in a carrier of hemophilia B.

A carrier of hemophilia B was found to have an unusually low factor IX level of 13 per cent. Her history of previous bleeding and the hospital course following elective dental extractions were consistent with a mild hemorrhagic diathesis. The patient is a member of a rare kindred of hemophiliacs. The mean level of factor IX in 12 carriers in this kindred was 42 per cent, with a range of 13 to 100 per cent. This patient represents the sixth reported case in which a female carrier of factor IX deficiency was symptomatic.

Gestational weight gain, pregnancy outcome, and postpartum weight retention.

OBJECTIVE: To determine whether the risk of maternal overweight associated with an excessive rate of gestational gain needs to be balanced against the risks of impaired fetal growth associated with a low rate of gain. METHODS: Rate of gestational weight gain was measured prospectively in a sample of 274 young, low-income, and primarily minority women (12-29 years old) with pregravid body mass indices (BMI) in the normal range (19.8-26.0). We defined an excessive rate of gain between 20-36 weeks' gestation as one greater than 0.68 kg/week, and a low rate of gain as one less than 0.34 kg/week. Women were followed-up at 4-6 weeks and 6 months postpartum. RESULTS: Rate of measured gestational gain between 20-36 weeks' gestation was associated with total weight gain based on pregravid weight, with infant birth weight and gestation duration, and with maternal overweight (BMI greater than 26) and weight retention postpartum. Infant birth weight and gestation duration were significantly reduced for women with low rates of gain, and there was no significant difference between women with excessive and moderate gains. Despite little difference in pregravid BMI, women with excessive rates of gain retained more weight overall, attained a greater postpartum BMI, and had higher levels of subcutaneous fat and overweight. Maternal anthropometric status showed little change between 4-6 weeks and 6 months postpartum. CONCLUSION: Weight gained at an excessive rate by women with a pregravid BMI in the normal range does not greatly enhance fetal growth and gestation duration, contributing instead to postpartum maternal overweight.

1-Methyl-4-(2'-methylphenyl)-1,2,3,6-tetrahydropyridine (2'CH3-MPTP)-induced degeneration of mesostriatal dopaminergic neurons in the mouse: biochemical and neuroanatomical studies.

The neurotoxic effects of 1-methyl-4-(2'-methylphenyl)-1,2,3,6-tetrahydropyridine (2'CH3-MPTP), a substituted analog of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, were studied in BALB/cJ mice. Moderate doses of 2'CH3-MPTP produced a greater depletion of dopamine (DA) in the striatum (45%) than in the nucleus accumbens (23%), and in these same animals, there was a 35% loss of midbrain DA neurons. The greatest loss of DA cells occurred within the substantia nigra (43%), and there was also a significant loss of cells within the ventral tegmental area (28%). Higher doses of 2'CH3-MPTP decreased levels of DA more in the axon terminal/forebrain region (72%) than in the cell body/midbrain region (25%). Similar forebrain/midbrain DA depletion ratios were also found in mice that received an electrolytic lesion of the midbrain DA neurons; there was a greater Da depletion in the forebrain (29%) than in the midbrain (8%). In both 2'CH3-MPTP and electrolytically lesioned animals there was a significant increase in DA turnover in the forebrain region, as measured by the homovanillic acid/DA ratio. These data indicate that 2'CH3-MPTP: (1) destroys DA neurons within two midbrain regions containing cells which project to the striatum (i.e. mesostriatal DA neurons), rather than just nigrostriatal DA neurons; (2) produces a greater loss of DA in the axon terminal region than in the cell body region; and (3) influences the mesostriatal DA neurons in the same way as does a lesion to the cell bodies. These data are discussed with regard to the pathophysiology of 2'CH3-MPTP.

The stress analogy.

The author calls attention to the advantages of using the engineering meaning of stress and strain when applying these terms to describe the effects of social and physical forces on people. Such an analogy opens up the possibility of measuring the amount of damage from excess stresses existing in people, as well as estimating their limits and remaining strengths. It also explains why some people are more affected by a given stressor than other people.

Analgesic effect of an aspirin-codeine-butalbital-caffeine combination and an acetaminophen-codeine combination in postoperative oral surgery pain.

The efficacy of an aspirin-caffeine-codeine-butalbital combination was compared to an acetaminophen-codeine combination and placebo in outpatients who had moderate or severe pain after the surgical removal of impacted third molars. Using a self-rating record, patients rated their pain, relief, anxiety and relaxation hourly for up to 6 hours after medicating. Each active medication was significantly superior to placebo for measures of analgesia and relaxation. Although the butalbital-containing combination provided consistently greater analgesia, the differences between active medications were not statistically significant. The acetaminophen-codeine combination significantly reduced anxiety; however, the butalbital containing combination did not. The results of this study suggest that female patients may have greater efficacy than male patients. All adverse effects were transitory and consistent with the known pharmacologic profiles of the study medications or the backup analgesic.

Evaluation of aspirin, caffeine, and their combination in postoperative oral surgery pain.

Three hundred fifty outpatients with postoperative pain after the surgical removal of impacted third molars were randomly assigned, on a double-blind basis, to receive a single oral dose of aspirin 650 or 1000 mg, caffeine 65 mg, a combination of aspirin 650 mg with caffeine 65 mg, or placebo. Using a self-rating record, subjects rated their pain and its relief hourly for 6 hours after medicating. Estimates of summed pain intensity difference, peak pain intensity difference, total relief, peak relief, and hours of 50% relief were derived from these subjective reports. All active treatments except caffeine were significantly superior to placebo. Pairwise comparisons indicated the aspirin-caffeine combination was statistically superior to aspirin 650 mg alone for hours of 50% relief among patients who had severe baseline pain. Adverse effects were transitory and none were serious.

Temperature and water relation patterns in subalpine understory plants.

The daily temperature and water relations of 7 perennial subalpine, understory species (1 shrub, 1 subshrub, 5 herbs) were compared in the Rocky Mountains of southeastern Wyoming with an emphasis on the effects of natural sun and shade exposure. Field measurements of rainfall; leaf, air, and soil temperatures; stomatal conductance to water vapor diffusion; and plant and soil water potentials were supplemented with leaf and root morphological measurements to evaluate potential adaptive patterns in understory species.Morphologically, all 7 species had relatively broad leaves that were hypostomous and bicolored with the abaxial leaf surface lighter than the abaxial surface. Root systems tended to be shallow (<20 cm), especially for the herbaceous species. Although soil water potentials from 4 to 40 cm depths remained relatively high throughout the summer (>-1.0 MPa), plant xylem water potentials for sunlit plants decreased to below-2.0 MPa during midday. During these sunlit periods, leaf temperatures and conductances increased substantially, leading to severe wilting for 4 of the 5 herbaceous species. Stomatal conductance and density for 6 of the 7 species monitored were much greater on abaxial compared to adaxial leaf sides and substantial stomatal closure occurred when either leaf side was oriented to receive direct sunlight. Moreover, stomatal opening on abaxial leaf sides corresponded to the amount of sunlight incident upon the adaxial rather than abaxial leaf surfaces. The 2 shrubby species did not wilt during these periods and were characterized by the highest leaf temperatures (>30°C). These 2 species also had consistantly lower xylem water potentials throughout the summer growth period. These results are discussed in terms of the possible adaptive significance of midday wilting, leaf hypostomy and bicoloration and stomatal behavior to the water and photosynthetic relations of understory species.

Leaf and environmental parameters influencing transpiration: Theory and field measurements.

The influence of variations in the boundary air layer thickness on transpirtion due to changes in leaf dimension or wind speed was evaluated at a given stomatal resistance (r s) for various combinations of air temperature (T a) and total absorbed solar energy expressed as a fraction of full sunlight (S ffs). Predicted transpiration was found to either increase or decrease for increases in leaf size depending on specific combinations of T a, S ffs, and r s. Major reductions in simulated transpiration with increasing leaf size occurred for shaded, highly reflective, or specially oriented leaves (S ffs=0.1) at relatively high T a when r s was below a critical value of near 500 s m-1. Increases in S ffs and decreases in T a lowered this critical resistance to below 50 s m-1 for S ffs=0.7 and T a=20°C. In contrast, when r s was above this critical value, an increase in leaf dimension (or less wind) resulted in increases in transpiration, especially at high T a and S ffs. For several combinations of T a, S ffs, and r s, transpiration was minimal for a specific leaf size. These theoretical results were compared to field measurements on common desert, alpine, and subalpine plants to evaluate the possible interactions of leaf and environmental parameters that may serve to reduce transpiration in xeric habitats.

Influence of sunflecks on the temperature and water relations of two subalpine understory congeners.

The temperature and water relations of the herbaceous, understory, congeners Arnica cordifolia and Arnica latifolia were evaluated in relation to the sunfleck dynamics of their respective microhabitats. Arnica cordifolia microhabitats had more frequent, longer, and more intense sunflecks than those of A. latifolia which led to higher leaf temperatures (31°C versus 15°C) and transpirational fluxes (65 µg cm-2 s-1 versus 16 µg cm-2 s-1). Stomatal closure did not occur in response to high leaf temperatures and low stem water potentials during natural sunfleck exposures, even though plants were observed to wilt during midday, especially A. cordifolia. Experimentally, an artificial midday sunfleck of about 165 min caused plants of A. cordifolia not to regain turgor after 8 h in shade compared to a sunfleck duration of about 90 min for plants of A. latifolia. However, these sunfleck intervals occurred naturally only during the early morning and late afternoon when solar intensities were minimal. Also, A. cordifolia populations had over twice as many plants that were sunlit (>40% of total) compared with A. latifolia (<20% of total) at any particular time during a day. The small-scale distribution of both species appears tightly coupled to the sunfleck dynamics of their respective microhabitats due to the lack of stomatal action which would reduce transpiration and improve plant water status under sunlit conditions.

Plant transpiration at high elevations: Theory, field measurements, and comparisons with desert plants.

The influence of elevational changes on plant transpiration was evaluated using leaf energy balance equations and well-known elevational changes in the physical parameters that influence water vapor diffusion. Simulated transpirational fluxes for large leaves with low and high stomatal resistances to water vapor diffusion were compared to small leaves with identical stomatal resistances at elevations ranging from sea level to 4 km. The specific influence of various air temperature lapse rates was also tested. Validation of the simulated results was accomplished by comparing actual field measurements taken at a low elevation (300 m) desert site with similar measurements for a high elevation (2,560 m) mountain research site. Close agreement was observed between predicted and measured values of transpiration for the environmental and leaf parameters tested.Substantial increases in solar irradiation and the diffusion coefficient for water vapor in air (D wv) occurred with increasing elevation, while air and leaf temperatures, the water vapor concentration difference between the leaf and air, longwave irradiation, and the thermal conductivity coefficient for heat in air decreased with increasing elevation. These changes resulted in temperatures for sunlit leaves that were further above air temperature at higher elevations, especially for large leaves. For large leaves with low stomatal resistances, transpirational fluxes for low-elevation desert plants were close to those predicted for high-elevation plants even though the sunlit leaf temperatures of these mountain plants were over 10°C cooler. Simulating conditions with a low air temperature lapse rate (0.003° C m-1 and 0.004° C m-1) resulted in predicted transpirational fluxes that were greater than those calculated for the desert site. Transpiration for smaller leaves decreased with elevation for all lapse rates tested (0.003° C m-1 to 0.010° C m-1). However, transpirational fluxes at higher elevations were considerably greater than expected for all leaves, especially larger leaves, due to the strong influence of increased solar heating and a greater D wv. These results are discussed in terms of similarities in leaf structure and plant habit observed among low-elevation desert plants and high-elevation alpine and subalpine plants.