Food-related energy requirements.

I have used data from input-output studies to determine the quantities of primary and electric energy consumed in the agricultural, processing, transportation, wholesale and retail trade, and household sectors for personal consumption of food. Before one draws conclusions from these results, it is important to note the assumptions and approximations used in this analysis. First, the economic input-output data published by the Department of Commerce are subject to a number of inaccuracies, including lack of complete coverage for an industry, restriction of data for proprietary reasons, and use of different time periods for different data. Second, aggregation can combine within the same sector industries whose energy intensities differ widely. For example, eating and drinking establishments probably consume more energy per dollar of sales (because of refrigerators, stoves, and freezers) than do department stores. However, both types of establishment are included in retail trade. Thus energy use for food-related retail trade may be underestimated because of aggregation. Third, the energy coefficients are subject to error. In particular, the coefficients for the agricultural and trade sectors are vulnerable because energy use within these sectors is not well documented. Finally, the scaling factor used to estimate food-related energy use for the 1960's is approximate, in that it neglects the possibility that these energy coefficients changed differently with time. Because of these limitations, which are described more fully by Herendeen (6), a number of important issues were not addressed here. such as relative energy requirements for fresh, frozen, and canned vegetables; and for soybeans as compared to beef. This analysis shows that the U.S. food cycle consumes a considerable amount of energy, about 12 percent of the total national energy budget. The residential sector, which accounts for 30 percent of the total, is the most energy-intensive sector in terms of energy consumed per dollar of food-related expenditure. This is because food-related expenditures in homes are primarily for fuel to operate kitchen appliances and automobiles. The electricity consumed in these activities constitutes 22 percent of the total amount used in the United States. More than half of the electricity is used in homes, and more than two-thirds in the trade and household sectors. Thus agriculture and processing consume little electricity relative to the total amount used. From past trends, it appears that the amount of energy used in food-related activities will continue to increase at a rate faster than the population, principally because of growing affluence, that is, the use of processed foods, purchase of meals away from home, and the use of kitchen appliances equipped with energy-intensive devices, such as refrigerators with automatic icemakers. However, fuel shortages, rapidly increasing fuel prices, the growing need to import oil, and a host of other problems related to our use of energy suggest that these past trends will not continue. Fortunately, there are many ways to reduce the amounts of energy used for food-related activities. In the home, for example, smaller refrigerators with thicker insulation would use less electricity than do present units. If closer attention were given to the use of ranges and ovens (for example, if oven doors were not opened so often) energy would be saved. Changes in eating habits could also result in energy savings. Greater reliance on vegetable and grain products, rather than meats, for protein would reduce fuel use. Similarly, a reduction in the amounts of heavily processcd foods consumed-TV dinners and frozen desserts-would save energy. Retailers could save energy by using closed freezers to store food and by reducing the amount of lighting they use. Processors could use heat recovery methods, more efficient processes, and less packaging. Shipping more food by train rather than by truck would also cut energy use. Farmers could reduce their fuel use by combining operations (for example, by harrowing, planting, and fertilizing in the same operation), by reducing tillage practices, by increasing thc use of diesel rather than gasoline engines, and by increasing labor inputs. A partial return to organic farming (that is, greater use of animal manure and crop rotation) would save energy because chemical fertilizers require large energy inputs for their production.

Efficiency of Energy Use in the United States: Transportation, space heating, and air conditioning provide opportunities for large energy savings.

We described three uses of energy for which greater efficiency is feasible: transportation, space heating, and air conditioning. Shifts to less energy-intensive transportation modes could substantially reduce energy consumption; the magnitude of such savings would, of course, depend on the extent of such shifts and possible load factor changes. The hypothetical transportation scenario described here results in a 22 percent savings in energy for transportation in 1970, a savings of 2800 trillion Btu. To the homeowner, increasing the amount of building insulation and, in some cases, adding storm windows would reduce energy consumption and provide monetary savings. If all homes in 1970 had the "economic optimum" amount of insulation, energy consumption for residential heating would have been 42 percent less than if the homes were insulated to meet the pre-1971 FHA standards, a savings of 3100 trillion Btu. Increased utilization of energy-efficient air conditioners and of building insulation would provide significant energy savings and help to reduce peak power demands during the summer. A 67 percent increase in energy efficiency for room air conditioners would have saved 15.8 billion kilowatt-hours in 1970. In conclusion, it is possible-from an engineering point of view-to effect considerable energy savings in the United States. Increases in the efficiency of energy use would provide desired end results with smaller energy inputs. Such measures will not reduce the level of energy consumption, but they could slow energy growth rates.

Effects of federal residential energy conservation programs.

We used a detailed engineering-economic simulation model of residential energy use to evaluate the effects of nine different residential energy-use "futures." These "futures" are described in terms of annual and cumulative energy use from 1977 through 2000 by fuel, end use, and in aggregate. Outputs from the model also include economic information on the costs to households of fuels, equipment, and thermal improvements to new and existing structures. The major outputs from these nine cases are shown in Tables 1 and 2 and Figs. 6 and 7.

Effects of energy conservation in residential and commercial buildings.

In 1977, heating, cooling, lighting, and other operations in residential and commercial buildings used 27 quads (1 quad = 10(15) British thermal units) of energy. This is more than one-third of the nation's total energy budget. Future trends in energy use in buildings are likely to depend strongly on fuel prices and government policies designed to save energy. Three scenarios are examined: (i) a base line in which fuel prices rise as projected by the Department of Energy; (ii) a conservation case that includes higher gas and oil prices plus the regulatory, financial incentive, and information programs authorized by the 94th Congress and proposed in the April 1977 National Energy Plan; and (iii) another conservation case that also includes new technologies (more efficient equipment, appliances, and structures). These scenarios are analyzed for changes in energy use, costs, and employment by means of detailed engineering-economic models of energy use in residential and commercial buildings developed at the Oak Ridge National Laboratory and input-output analyses developed at the University of Illinois.

Managing state energy conservation programs: the Minnesota experience.

In fiscal year 1980, the Department of Energy awarded grants for state energy conservation programs that totaled more than $400 million; the proposed figure for fiscal year 1981 is almost $600 million. Many states provide additional funds to implement conservation programs. This suggests that state governments play a major role in delivering conservation services to their citizens and are key agents in the nation's conservation efforts. This article discusses the energy conservation activities and responsibilities of one state energy office, the Minnesota Energy Agency, and the obstacles and constraints it faces in delivering its services. Suggestions are presented for resolving these difficulties and for improving the efficiency with which the agency manages its programs.

2-Aminopurine abolishes EGF- and TPA-stimulated pp33 phosphorylation and c-fos induction without affecting the activation of protein kinase C.

Epidermal Growth Factor (EGF) and Tetradecanoyl Phorbol Acetate (TPA) initiate signalling cascades in C3H 10T1/2 fibroblasts by primarily activating distinct protein kinases, the EGF receptor tyrosine kinase and protein kinase C respectively; there is no signal crossover at the initiation of signalling. Nevertheless, we show here that both agents rapidly elicit common intracellular responses, including the phosphorylation of complexed and chromatin-associated forms of a 33 kDa phosphoprotein (pp33), that of a 15 kDa chromatin-associated phosphoprotein (pp15), as well as the transcriptional activation of a common subset of genes including the c-fos proto-oncogene. 2-aminopurine specifically abolishes complexed and chromatin-associated pp33 phosphorylation in response to EGF and TPA, as well as the induction of c-fos by both agents. The activation of protein kinase C and the levels of transcription factors that bind to the serum response element (SRE), TPA response element (TRE) or NFkB sites in stimulated cells are relatively unaffected by 2-aminopurine. This, to our knowledge, is the first demonstration that it is possible, by using 2-aminopurine which selectively blocks TPA-stimulated pp33 phosphorylation, to block c-fos induction in TPA-treated cells although protein kinase C remains fully active. Further, we show here that although EGF- and TPA-stimulated induction of c-fos is abolished by 2-aminopurine, the appearance of TRE-binding activity in nuclear extracts of stimulated cells is unaffected, suggesting that EGF- and TPA-stimulated induction of TRE-binding activity utilises existing proteins and is not dependent on fresh c-FOS synthesis. These results imply that 2-aminopurine-sensitive complexed and chromatin-associated pp33 phosphorylation may be crucial to c-fos induction in response to EGF and TPA.

Rapid appearance of novel phosphoproteins in the nuclei of mitogen-stimulated fibroblasts.

A sequential extraction procedure has been used to prepare three protein fractions from control and mitogen-stimulated [32P]-PO4-labelled fibroblasts, the first containing soluble and membrane-bound proteins, the second mainly the cytoskeletal proteins vimentin and actin, and the third, a chromatin-derived fraction enriched in histones. We describe here an analysis of the mitogen-stimulated changes in the [32P] labelled phosphoprotein composition of these fractions. The most obvious changes in response to epidermal growth factor, embryonal carcinoma-derived growth factor, basic fibroblast growth factor and bombesin were the rapid appearance of 33 and 15 kDa phosphoproteins in the chromatin-derived fraction. The epidermal growth factor- and basic fibroblast growth factor-stimulated 33 kDa phosphoprotein produced similar chymotryptic peptides and was phosphorylated on serine residues. DNAse/RNAse treatment of the lysates was essential for the extraction of the 33 kDa phosphoprotein. Further, its presence could be demonstrated in preparations of conventionally purified nuclei. An in situ extraction procedure has been used to provide morphological verification of the sequential extraction data. The final structure containing these phosphoproteins is clearly derived from nuclei, enriched in histones, stains for DNA and appears by electron microscopy, to be homogenously composed of chromatin-like material. Thus, we describe here the rapid mitogen-induced appearance of novel phosphoproteins in the nucleus, raising the possibility that they may be involved in orchestrating early nuclear responses to polypeptide growth factors.

Are beta 1 integrins involved in Xenopus gastrulation?

The molecular basis of vertebrate gastrulation is poorly understood. Work on urodele amphibians has implicated beta 1-containing integrins, but the limited information available for Xenopus indicates otherwise: peptides containing the RGD sequence do not inhibit gastrulation and induction of cell spreading in presumptive ectodermal cells by activin is not accompanied by an increase in synthesis of integrin beta 1. Here we report that beta 1-containing integrins are, nevertheless, the principal fibronectin receptors in the Xenopus gastrula, although their cell surface levels are low. Antibodies recognizing the external domain of the molecule can, unlike peptides containing the RGD site, block gastrulation when introduced into the blastocoel. These results allow us to propose a model to explain the role of integrin beta 1 in Xenopus gastrulation.

Single particle multichannel bio-aerosol fluorescence sensor.

We describe a prototype low-cost multi-channel aerosol fluorescence sensor designed for unattended deployment in medium to large area bio-aerosol detection networks. Individual airborne particles down to ~1mum in size are detected and sized by measurement of light scattered from a continuous-wave diode laser (660nm). This scatter signal is then used to trigger the sequential firing of two xenon sources which irradiate the particle with UV pulses at ~280 nm and ~370 nm, optimal for excitation of bio-fluorophores tryptophan and NADH (nicotinamide adenine dinucleotide) respectively. For each excitation wavelength, fluorescence is detected across two bands embracing the peak emissions of the same bio-fluorophores. Current measurement rates are up to ~125 particles/s, corresponding to all particles for concentrations up to 1.3 x 104 particles/l. Developments to increase this to ~500 particles/s are in hand. Device sensitivity is illustrated in preliminary data recorded from aerosols of E.coli, BG spores, and a variety of non-biological materials.

SufC hydrolyzes ATP and interacts with SufB from Thermotoga maritima.

Genetic experiments in bacteria have shown the suf operon is involved in iron homeostasis and the oxidative stress response. The sufB and sufC genes that always occur together in bacteria are also found in plants, and even the malaria parasite, associated with the plastid organelle. Although the suf operon is believed to encode an iron-dependent ABC-transporter there is no direct evidence. By immunolocalization we show here that SufB and SufC are associated with the membrane of Escherichia coli. We also present kinetic studies with a recombinant version of SufC from Thermotoga maritima that shows it is an ATPase and that it interacts with SufB in vitro.

Bacterial orthologues indicate the malarial plastid gene ycf24 is essential.

ycf24 is a well conserved gene found in all major groups of bacteria, as well as on red algal plastid genomes and the vestigal plastid genome of apicomplexan pathogens like the malaria parasite Plasmodium falciparum (ORF470). Some database annotations describe Ycf24 as an ABC transporter subunit, but we find the level of significance is low. To investigate ycf24's function we disrupted it in the cyanobacterium Synechocystis sp., strain PCC6803 which has a multi-copy genome. This showed ycf24 is essential, partial loss producing a terminal phenotype of chlorosis, reduced cell size, loss of DNA, and a striking arrest in cytokinesis. Attempts to disrupt the single copy of ycf24 in E. coli failed to give stable transformants. When Ycf24 was over-expressed in E. coli as a soluble fusion protein, it localized mostly as a band on either side of the nucleoid and nucleoid partitioning was aberrant. We propose the relict plastid organelle of apicomplexans retains its capacity for protein synthesis because Ycf24 is essential.

Real-time observation of the change in light scattering from droplets with increasing deformity.

Commercial aerodynamic particle sizing instruments generally achieve the desired particle size measurement by accelerating a sample airstream in which the particles are suspended and measuring the velocity acquired by individual particles. The accelerating flow regime can cause liquid droplets to deform and this subsequently introduces errors. In this paper, we present an apparatus that enables droplet deformation to be observed by recording the spatial light scatter intensity. The paper presents experimental data in video format showing the changes that occur in the light scattering from droplets as a function of increasing flow rate/deformation.

Improved post-embedding immunocytochemistry of myelinated nervous tissue for electron microscopy.

The particularly high lipid content of normal mature adult myelin sheaths, together with the light fixation protocols usually necessary to retain antigenicity, combine to make white matter nervous tissue an especially problematical subject for post-embedding immuno-electron microscopy using modern acrylic resins. Fixation and infiltration modifications to standard processing schedules for Lowicryl were found to greatly improve the embedding and therefore the resulting morphology. This in turn improved the signal to noise ratio by reducing the high non-specific backgrounds usually found in poorly infiltrated areas. Using Lowicryl HM20, we have been able to obtain satisfactory immunostaining for myelin basic protein with good retention of structural integrity in the myelin of both normal and lesioned adult cortico spinal tract.

Perturbations of the topography of the tegument of adult Schistosoma mansoni. A scanning electron microscope study.

1. Adult Schistosoma mansoni show a proclivity to release fragments of the tegumental surface membrane when they are incubated in various media, or after they are exposed to positively charged microspheres. Scanning electron microscopy was used to examine the extent and nature of the perturbations induced by the two treatments used to prepare tegumental membranes. 2. Incubation of the parasites in a phosphate-buffered medium resulted in extensive blebbing and release of vesicles from the tegument. 3. Attachment of positively charged microspheres followed by their release yielded tegument membrane fragments of a different morphology. 4. The nature and implications of these perturbations to membrane processes occurring at the tegument of schistosomes are discussed.

Postnatal depression across countries and cultures: a qualitative study.

BACKGROUND: Postnatal depression seems to be a universal condition with similar rates in different countries. However, anthropologists question the cross-cultural equivalence of depression, particularly at a life stage so influenced by cultural factors. AIMS: To develop a qualitative method to explore whether postnatal depression is universally recognised, attributed and described and to enquire into people's perceptions of remedies and services for morbid states of unhappiness within the context of local services. METHOD: The study took place in 15 centres in 11 countries and drew on three groups of informants: focus groups with new mothers, interviews with fathers and grandmothers, and interviews with health professionals. Textual analysis of these three groups was conducted separately in each centre and emergent themes compared across centres. RESULTS: All centres described morbid unhappiness after childbirth comparable to postnatal depression but not all saw this as an illness remediable by health interventions. CONCLUSIONS: Although the findings of this study support the universality of a morbid state of unhappiness following childbirth, they also support concerns about the cross-cultural equivalence of postnatal depression as an illness requiring the intervention of health professionals; this has implications for future research.

Ultrastructural localization of Sm15 and Sm25, two major tegumental adult worm antigens of Schistosoma mansoni.

Sm15 and Sm25 are two of the principal tegumental antigens recognized by antibodies from mice protectively vaccinated with adult worm tegumental membranes and may therefore be potential vaccine candidate antigens. Using antibodies affinity purified from anti-tegumental membrane anti-sera, and antibodies raised against the recombinant antigens, Sm15 and Sm25 were shown to be located specifically in the tegument of adult worms being distributed throughout the syncitium but not associated with the outer membrane.

Hospital characteristics affecting potentially avoidable emergency admissions: national ecological study.

Some emergency admissions can be avoided if acute exacerbations of health problems are managed by emergency and urgent care services without resorting to admission to a hospital bed. In England, these services include hospitals, emergency ambulance, and a range of primary and community services. The aim was to identify whether characteristics of hospitals affect potentially avoidable emergency admission rates. An age-sex adjusted rate of admission for 14 conditions rich in avoidable emergency admissions was calculated for 129 hospitals in England for 2008-2011. Twenty-two per cent (3,273,395/14,998,773) of emergency admissions were classed as potentially avoidable, with threefold variation between hospitals. Explanatory factors of this variation included those which hospital managers could not control (demand for hospital emergency departments) and those which they could control (supply in terms of numbers of acute beds in the hospital, and management of non-emergency and emergency patients within the hospital). Avoidable admission rates were higher for hospitals with higher emergency department attendance rates, higher numbers of acute beds per 1000 catchment population and higher conversion rates from emergency department attendance to admission. Hospital managers may be able to reduce avoidable emergency admissions by reducing supply of acute beds and conversion rates from emergency department attendance.