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Preparation des copolymeres a partir d'oligomeres xylenyl ethers termines par un groupe silyloxy et d'oligomeres de sulfone termines par un groupe fluoro phenyl avec le CsF comme catalyseur; l'oligomere de sulfone est prepare par reaction du bisphenol A avec la difluoro-4,4' phenylsulfone. La faisabilite de la reaction est verifiee par une polymerisation modele de la difluoro-4,4' phenylsulfone avec le tetramethylbisphenol o-silyle

The microwave spectrum of chloromethylphosphonic difluoride, ClCH2P(O)F2, has been investigated in the region from 26.5 to 39 GHz. The a‐type R branch transitions have been assigned for both the 35Cl and 37Cl isotopic species for the trans conformer on the basis of the rigid rotor model. For the ground vibrational state the rotational constants for the 35Cl isotope were found to be A = 4392.4±2.3, B=1543.36±0.01, and C=1512.30±0.01 MHz and for the 37Cl isotope: A=4395.3±2.7, B=1502.04±0.01, and C=1472.54±0.01 MHz. With reasonably assumed structural parameters for the C–H and P=0 distances as well as the HCH angle, a diagnostic least‐squares adjustment was utilized to obtain the other six structural parameters. The dipole moment components were determined from the Stark effect to be ‖μa‖ =2.28±0.05, ‖μb‖ =0.75±0.02, and ‖μt‖ =2.40±0.02 D. The infrared (3500–40 cm−1) and Raman (3500–20 cm−1) spectra of the gas and solid have been recorded. Additionally, the Raman spectrum of the liquid has been recorded and...

The cutaneous innervation of the fo relimb was investigated in 20 bar-biturate-anesthetized cats by using electrophysiological techniques. The cutaneous area (CA) innervated by each cutaneous nerve was delineated in at least six cats by brushing the hair in the CA with a small watercolor brush while recording from the nerve. Mapping of adjacent CA revealed larger overlap zones (OZ) than were noted in the dog. Remarkable findings were that the brachiocephalic nerve arose from the axillary nerve and the CA comparable to that supplied by the cutaneous branch of the brachiocephalic nerve in the dog was supplied by a cutaneus branch of the suprascapular nerve. The CA supplied by the communicating branch from the musculocutaneous to the median nerve was similar in both species except that the communicating branch arose proximal to any other branches of the musculocutaneous nerve in the cat, whereas it was a terminal branch in the dog. The superficial branch of the radial nerve gave off cutaneous brachial branches in the cat proximal to the lateral cutaneous antebrachial nerve. The CA of the palmar branches of the ulnar nerve did not completely overlap the CA of the palmar branches of the median nerve as occurred in the dog; thus an autonomous zone (AZ) for the CA of the palmer branches of the median nerve is present in the cat, whereas no AZ existed for the CA of this nerve in the dog.

The Prostatic-Group-Label Immunoassay (PGLIA) technique has been incorporated into a reagent-strip format. We report use of flavin N6-(N'-2,4-dinitrophenyl-6-aminohexyl)adenine dinucleotide (DNP-FAD) as the prosthetic group derivative and 6-N-(2,4-dinitrophenyl)aminohexanoic acid (DNP-caproate) as the competing ligand. DNP-FAD not bound by antibody combines with glucose oxidase apoenzyme, which then reacts with glucose and oxygen, and gives color through a peroxidase-linked system. The rate of color generation is thus a function of the DNP-caproate concentration. PGLIA reagent strips are prepared by sequential impregnations of filter paper with an acetone solution of indicator (3,3',5,5'-tetramethylbenzidine); an aqueous solution containing glucose oxidase apoenzyme, the rest of the color generation system, stabilizers, and antibody to DNP; and a solution of DNP-FAD in n-propanol. This preparation permits effective antibody binding, and prevents premature interaction of immunoassay components. A quantitative color response to concentrations of DNP-caproate in the range of 1 to 8 mumol/L was demonstrated with these reagent strips. Prototype PGLIA reagent strips for theophylline and phenytoin have been successfully developed by substituting the appropriate FAD derivative and antibody for the corresponding reagents in the DNP model system.

In the dog, we isolated 126 mechanoreceptive afferent fibers of the A-delta myelinated fiber class from the dorsal nerve of the penis using microdissection and extracellular electrophysiological techniques. Receptive fields on the glans penis were stimulated with a computer-controlled mechanostimulator and Peltier effect thermostimulator. The great majority of units were categorized as either rapidly adapting (RA) or slowly adapting (SA) and were located primarily proximally and distally, respectively, on the glans. In comparison to values from other glabrous skin regions in other species, mean displacement and force thresholds of penile mechanoreceptors were high, whereas the mean velocity thresholds were low. SA units, generally poor encoders of static displacement, were distinguishable into two types based on static response firing pattern but were not homologous to either the SA I or SA II mechanoreceptors found in other skin regions. Fifty-five units were given simultaneous mechanical and thermal stimulation. Very few units responded to pure thermal stimulation or increased their discharge frequency to skin cooling. Warm receptive-field temperatures between 35 and 43 degrees C increased mechanical sensitivity, measured by displacement and velocity coding functions, in almost all units tested. We conclude that canine penile mechanoreceptors, capable of encoding a variety of skin movements when the penis is warm, provide the spinal cord with the sensory input necessary to drive the spinal sexual reflexes. However, many appear to be at least physiologically different from mechanoreceptors native to other skin areas.

A senior year experience similar to an internship was initiated in community hospitals. It is designed to shorten the overall length of training and to restore a broad-based clinical experience to the period of "intermediate patient care responsibility" in the training of new physicians. The program provides students with an opportunity to observe and practice in a primary care setting and expands the clinical resources of the medical school. Analysis of the performance of students in the class of 1974 indicates that they perform on a level comparable with first-year house officers. This program provides a general clinical experience for those students who have not yet decided on future training plans or who are going into primary care fields.

The microwave spectra of 11 chemically different isotopic species of ethylphosphine (CH3CH2PH2) including all 13C and D single substituted species were recorded and assigned for the vibrational ground state. The b‐ and c‐type transitions of the gauche conformers with symmetrically substituted ethyl groups and a PH2 group were found to be split due to tunneling between the equivalent forms. The spectra of these molecules were fit to a Hamiltonian containing Coriolis interaction terms. All other spectra were fit to asymmetric rotors with quartic centrifugal distortion. Complete rs structures were obtained for both the trans and gauche conformations. The r0 structures were derived from 45 and 48 rotational constants for the trans and gauche forms, respectively. Significant differences in the structures were found with the most notable one in the CCP angle which changes from 110.5° in the gauche form to 116° in the trans conformer. The methyl group in the gauche conformation is rotated away from a position sy...

Experimental observations have been made at temperatures up to 1450 degrees C and pressures up to 0.2 GPa of the density of expanded liquid mercury, and the electrical conductivity of liquid mercury and of certain amalgams, chiefly Hg-3 at.% In and Hg-1 to 3 at.% Na. The density of a 3 at.% In amalgam was also measured over the same pressure range to 1000 degrees C. The data lead to some discussion of the effect of the solute on compressibility, expansivity, volume and conductivity. The decrease of conductivity caused by Na at high mercury densities is shown to change to a large decrease near the metal-insulator transition density, though the mechanism remains obscure.

The microwave spectra of ethylphosphonothioic difluoride, CH3CH2P(S)F2, and eight isotopic species have been investigated in the region from 26.5 to 39.5 GHz. Only a‐type transitions were observed and R‐branch assignments have been made for all the isotopic species in the ground vibrational state for both the gauche and trans (methyl group trans to the P=S bond) conformers from which the rotational constants were determined. From these data the complete r0 structural parameters were determined for the gauche conformer with the values for the heavy atom parameters being: r(C–C)=1.532±0.006 A, r(C–P)=1.800±0.007 A, r(P=S)=1.880±0.003 A, r(P–F)=1.555±0.005 A, ∢CCP=112.6±0.3°, ∢CPS=119.4±0.4°, ∢CPF=102.0±0.2°, dih ∢FPCS=129.3±0.2°, and dih ∢CCPS=56.9±0.2°. The parameters of the trans conformer which differed significantly from the values for the corresponding ones in the gauche conformer were: r(C–P)=1.814±0.011 A, r(P=S)=1.861±0.007 A, and ∢CCP=114.8±0.2°. The infrared (3500 to 40 cm−1) and Raman (3500 to 20...

To predict the critical parameters of plutonium fueled systems one must establish the accuracy of the computational methods to be employed and the accuracy and applicability of the available critical experiment data with which the calculations are to be compared. The accuracy of a multigroup diffusion theory code, HFN, and a multigroup transport theory code, DTF-IV, was examined by analyzing recent plutonium critical experiments. The experiments cover the entire range of possible moderation ratios, and the plutonium fuels contain as much as 23.2 isotopic percent 240Pu. All three basic geometries are represented by the experimental data examined. Where necessary, the criticality data were corrected, by means of additional experiments and/or calculations, to conform to one-dimensional, clean, homogeneous critical assemblies which could be adequately defined and used as a basis for establishing nuclear criticality safety guidelines.

Radioactive tracer techniques have been utilized to measure the rate of diffusion of gold into polycrystal‐line copper over the temperature range from 1000° to 375°C. These experiments have yielded the values Q=44 900±1300 cal/mole and D0=0.10±0.06 cm2/sec for the volume diffusion process in the temperature range from 1000°C to 750°C. Diffusion measurements at 550°C and 375°C indicated that the measured rates at these temperatures had been enhanced by grain‐boundary diffusion. Considerable attention was directed toward the variation of the diffusion coefficient with (1) the purity of the copper, (2) the grain size of the copper, (3) the thickness of the plating, and (4) the time of anneal. Variations of these parameters showed no significant effect on the diffusion coefficient, with the exception of the time of anneal. The measured diffusion rate at 1000°C was observed to decrease with increasing time of anneal.

Radioactive tracer techniques have been employed to measure the rate of self‐diffusion in silver in polycrystalline and single crystal solvents over a wide range of temperatures, and to investigate the effect of bombardment with 10‐Mev protons on this diffusion process. A least squares fit of the data from laboratory control experiments with both single crystal and polycrystalline solvents in the temperature range 903°C to 640°C has yielded the diffusion constants Q=40,800±700 cal/mole and D0=0.11±0.05 cm2/sec for the volume diffusion process. No effect of intense proton bombardment ranging from 0.5 to 5μa/cm2 has been detected on the volume self‐diffusion process in silver specimens which were simultaneously irradiated in the cyclotron target box and annealed at temperatures ranging from 852°C to 555°C. These results are, at least semiquantitatively, in accord with both the elastic collision model and the thermal spike model of radiation damage. Cyclotron techniques and apparatus are described in some de...

Resonant Elastic X-Ray Scattering (REXS) has played a fundamental role in understanding electronic properties and in revealing hidden order, local symmetries and exotic states realized in correlated solids. This article reports on some of the relevant scientific contributions and technical advances over the last 20 years, by providing a list of related publications produced by various groups all around the world. The given perspective is that of a group of young scientists involved at various times in the investigation of the beauty of electronic ordering by the REXS technique. © 2012 EDP Sciences, Springer-Verlag.

A sample of patients (N = 134) with alcoholic liver disease was found to be significantly "health internal" (i.e., believe that their behavior plays a major role in determining subsequent health or illness) compared with a sample of patients with nonalcoholic liver disease on Health Locus of Control Scale. The patients with alcoholic liver disease did not differ significantly from those with nonalcoholic liver disease in the level of awareness of severity of their disease. Most patients in both groups agreed with their physician's ratings of the severity of their illness. The implications of these findings are discussed.

WHEN L-3,4-dihydroxyphenylalanine (L-dopa) is administered to human subjects1, the greater proportion is metabolised by decarboxylation, a small amount by O-methylation and traces only by transamination2. It seems likely that the benefit resulting from L-dopa therapy in Parkinsonian patients derives largely from the generation of one of its metabolites, dopamine, by decarboxylation within the central nervous system3. Less than 5% of administered L-dopa becomes available for this purpose: most of the dose is decarboxylated peripherally4. There is good reason to believe that the dopamine so formed is unable to penetrate the blood-brain barrier to any great extent5, so that little of the original dose is available to contribute to the therapeutic response. By blocking peripheral decarboxylase, however, certain decarboxylase inhibitors6,7, which are themselves unable to cross the blood-brain barrier to any significant extent8, bring about an accumulation in the plasma of administered L-dopa, thus providing a higher concentration gradient to enter the central nervous system and allowing lower oral doses of L-dopa to be employed therapeutically9.

The object of this paper is to establish the equivalence of four functionrelated dimension concepts in arbitrary topological spaces. These concepts involve stability of functions (3, p. 74), the modification of covering dimension involving basic covers (1, p. 243) (which is equivalent to Yu. M. Smirnov's definition using normal covers), the definition involving essential mappings (2, p. 496), and a modification of the closed set separation characterization of dimension in (3, p. 35).

This report is on the twelfth in the series on the presence of pesticide and other chemical residues in the average diet of the United States' heartiest eater, the young adult male. Twenty market baskets were collected in 20 U.S. cities that ranged in population from less than 50,000 to 1 million or more. Composites of 12 food classes were analyzed. Averages and ranges of residues found are reported for August 1975 through July 1976, by food class. In addition to the pesticide and chemical residues, data for lead, cadmium, selenium, mercury, arsenic, and zinc are included. The individual items making up the dairy and meat composites in four market baskets were analyzed separately for pesticide residues, and the results are included. Results of recovery studies of pesticides and chemicals within various food classes are also presented.

The meeting of the Council on Rehabilitation of the International Society of Cardiology held in 1968 in Sardinia, Italy, gave a much needed impetus for an international survey of the psycho-social aspects of cardiac rehabilitation. The meeting of the Council in Vienna in 1971 was a milestone of achievement because the most useful contribution to date concerned with cardiac rehabilitation is the published proceedings (1) of that Vienna meeting. The Chairman of the Council, Prof. H. Denolin, refers to the proceedings as a handbook “of interest to all practitioners involved in prevention or rehabilitation whether they be physicians, nurses, psychologists, dietitians or physical medinice experts”. In his preface, Prof. Denolin acknowledges the differing approaches to rehabilitation but points out that “most specialists agree to its importance and that the concept of a medico-social team acting early in the illness and continually is a worthwile advance in this sphere”.

An 80-year-old woman developed acute hepatitis following her first exposure to nifedipine. This adverse effect was characterised by fever, chills, anorexia, nausea, liver tenderness, hepatitic liver function tests and peripheral blood eosinophilia. On liver biopsy the portal tracts were expanded with a mixed inflammatory cell infiltrate rich in eosinophils. The potential for the occurrence of this adverse effect must increase with the current expansion of indications for the use of nifedipine.

Since 1964 the Food and Drug Administration Total Diet study has reported residues of pesticides and other chemicals ingested in the diet of a young adult male, statisically the Nation's largest eater. During the tenth year of the study, pesticide residues remained at the relatively low levels previously reported. Thirty market baskets were collected in 30 cites which ranged in population from less than 50,000 to 1,000,000 or more. Averages and ranges of residues are reported from August 1973 through July 1974 by food class. Individual items in the dairy and meat composites in four market baskets were analyzed for pesticides; results are included. Data for lead, cadmium, selenium, mercury, arsenic, and zinc are also included. Results of recovery studies within various classes of residues are also presented.

In the L-Dopa treated rat, a decreased urinary output of free and conjugated dopamine and an increase in free and conjugated L-Dopa excretion after administration of decarboxylase-inhibiting drugs provide a good in vivo index of Dopa decarboxylase inhibition. With the exception of free dopamine output, which showed an equivocal change, these measurements appear to provide a good yardstick of decarboxylase status in man also. Using this approach, it was not possible to find any evidence of facilitation of decarboxylase action, in L-Dopa-treated parkinsonians given pyridoxine supplements, to account for the ability of this compound to neutralize the beneficial effect of L-Dopa.

The properties of alpha-1 adrenergic receptors in rat cerebral cortex were examined by measuring increases in [3H]inositol metabolism in brain slices. Slices of rat cerebral cortex were incubated in the presence of 0.23 microM [3H]inositol in Krebs-Ringer-bicarbonate buffer containing 10 mM lithium chloride, and the production of water-soluble [3H]inositol phosphates was monitored after extraction and anion-exchange chromatography. Norepinephrine caused a 4- to 6-fold increase in [3H]inositol metabolism in cerebral cortical slices, and this response was blocked much more potently by the alpha-1-selective antagonist prazosin than by the alpha-2-selective antagonist yohimbine. Epinephrine and norepinephrine were both full agonists and stimulated [3H]inositol metabolism to the same extent in this system. The synthetic drugs phenylephrine and methoxamine were both partial agonists at these receptors, with intrinsic activities only 56 to 58% of epinephrine and norepinephrine. A variety of imidazoline and other partial agonists caused no measurable stimulation of [3H]inositol metabolism in this preparation. The response to norepinephrine was completely blocked by alpha adrenergic receptor antagonists with the potency order prazosin greater than BE 2254 greater than indoramin = phentolamine greater than azapetine greater than piperoxan greater than yohimbine. In the absence of calcium, basal [3H]inositol metabolism was increased, but norepinephrine caused the same 5-fold stimulation as in the presence of 2.5 mM CaCl2. The potencies of both antagonists and agonists in inhibiting or activating [3H]inositol metabolism in slices of rat cerebral cortex were highly correlated with their ability to displace the alpha-1 adrenergic receptor selective radioligand [125I]BE 2254 from specific binding sites in membrane preparations of rat cerebral cortex.(ABSTRACT TRUNCATED AT 250 WORDS)

Since 1964, the Food and Drug Administration, U.S. Department of Health, Education and Welfare, has reported residues of pesticides and other chemicals present in the average diet of the young adult male. The present report is the first in a series of market baskets whose purpose is to monitor the average diet of infants and toddlers for the same residues. Ten market baskets were collected in 10 cities which ranged in population from less than 50,000 to 1,000,000 or more. Averages and ranges of residues found are reported by food class. Results of recovery studies of known residues and chemicals within various food classes are also presented.

The Prostatic-Group-Label Immunoassay (PGLIA) technique has been incorporated into a reagent-strip format. We report use of flavin N6-(N'-2,4-dinitrophenyl-6-aminohexyl)adenine dinucleotide (DNP-FAD) as the prosthetic group derivative and 6-N-(2,4-dinitrophenyl)aminohexanoic acid (DNP-caproate) as the competing ligand. DNP-FAD not bound by antibody combines with glucose oxidase apoenzyme, which then reacts with glucose and oxygen, and gives color through a peroxidase-linked system. The rate of color generation is thus a function of the DNP-caproate concentration. PGLIA reagent strips are prepared by sequential impregnations of filter paper with an acetone solution of indicator (3,3',5,5'-tetramethylbenzidine); an aqueous solution containing glucose oxidase apoenzyme, the rest of the color generation system, stabilizers, and antibody to DNP; and a solution of DNP-FAD in n-propanol. This preparation permits effective antibody binding, and prevents premature interaction of immunoassay components. A quantitative color response to concentrations of DNP-caproate in the range of 1 to 8 mumol/L was demonstrated with these reagent strips. Prototype PGLIA reagent strips for theophylline and phenytoin have been successfully developed by substituting the appropriate FAD derivative and antibody for the corresponding reagents in the DNP model system.

The density and functional responsiveness of adrenergic receptor subtypes were determined in tissues from control, hyperthyroid and hypothyroid rats. There was a decrease in sensitivity to isoproterenol in spontaneously beating right atria, electrically driven left atria and field-stimulated vas deferens associated with hypothyroidism, with no change in maximum response. Hyperthyroidism increased the potency of isoproterenol in right atria, but not in left atria or vas deferens. The maximal response to isoproterenol was greatly reduced in hyperthyroid left atria. The potency of procaterol, a partial agonist at beta adrenergic receptors in right atria, was unaltered in hyper- or hypothyroidism, although the maximum stimulation by procaterol was increased in hyperthyroidism. Scatchard analysis of specific [125I]pindolol binding showed that beta adrenergic receptor density was greater in hyperthyroidism than in hypothyroidism in left atria, right atria, ventricles, vas deferens and cerebral cortex, although the proportions of beta-1 and beta-2 adrenergic receptor subtypes did not change. There was no change in the responsiveness of alpha-1 adrenergic receptors mediating contraction of caudal artery and vas deferens or mediating [3H]inositol phosphate accumulation in cerebral cortex in hyperthyroid or hypothyroid rats, although the maximal contraction of caudal artery was significantly reduced in hyperthyroidism. Scatchard analysis of specific [125I]BE 2254 binding showed that alpha-1 adrenergic receptor density was significantly decreased in the ventricles from hyperthyroid rats and increased in the ventricles of hypothyroid rats, but was unchanged in vas deferens, caudal artery and cerebral cortex. Alpha-2 adrenergic receptor density in cerebral cortex, determined by Scatchard analysis of specific [3H] rauwolscine binding, was not altered in hyperthyroid or hypothyroid rats.(ABSTRACT TRUNCATED AT 250 WORDS)

During the eighth year of the Total Diet Study, residues remained at the relatively low levels reported previously. A total of 35 market baskets were collected in 32 cities which ranged in population from less than 50,000 to 1,000,000 or more. Averages and ranges of residues found are reported for the period June 1971 through July 1972 by region and food class. Results of recovery studies within various classes of residues are also presented.

Activation of alpha 1-adrenergic receptors in slices of rat brain increases inositol phosphate accumulation, increases basal cyclic AMP accumulation, and potentiates the increase in cyclic AMP caused by adenosine. We compared these three responses to determine whether they are mediated by the same receptors. The increase in inositol phosphates and the potentiation of cyclic AMP accumulation in cerebral cortex were largely blocked by chelation of extracellular calcium, whereas the increase in basal cyclic AMP was not affected. The magnitude of the increase in inositol phosphates in different brain regions correlated with the magnitude of the potentiation of cyclic AMP accumulation (r = 0.80), but neither of these correlated with the magnitude of the increase in basal cyclic AMP. Although other alkylating agents inactivated all of the alpha 1-adrenergic receptor-binding sites labeled with 125IBE 2254 in membrane preparations of cerebral cortex, chlorethylclonidine (CEC) potently and selectively inactivated only half of these sites. Pretreatment with CEC partially blocked the increase in basal cyclic AMP, but not the increase in inositol phosphates or potentiation of cyclic AMP accumulation in slices of cerebral cortex. Comparing different brain regions, there was a better correlation between the density of 125IBE 2254-binding sites not inactivated by CEC with the magnitude of the increase in inositol phosphates or potentiation of cyclic AMP accumulation than with the increase in basal cyclic AMP. Although the largest increase in inositol phosphates was observed in slices of hippocampus, there was only a small increase in basal cyclic AMP in this region, and CEC did not inactivate any 125IBE-binding sites in hippocampus. Phentolamine and WB 4101 were significantly more potent in inhibiting specific 125IBE 2254 binding in hippocampus than in cerebral cortex. After treatment of cerebral cortical membranes with CEC, however, these drugs had potencies similar to those observed in hippocampus. The results suggest that the alpha 1-adrenergic receptors mediating increases in basal cyclic AMP accumulation can be differentiated from those mediating increases in inositol phosphate accumulation and potentiating adenosine stimulated cyclic AMP accumulation by their binding properties, calcium dependency, regional distribution, and sensitivity to the alkylating agent CEC.

The spinal nerve root origins of the cutaneous nerves arising from the brachial plexus were investigated in 10 babiturate-anesthetized dogs by stimulating dorsal roots C5 to T2 and recording from each cutaneous nerve. Upon completion of the experiment, the contributions of the spinal nerve ventral branches to the brachial plexus were verified by anatomic dissection. The brachial plexus was formed by the ventral branches of C6 to T2 in 8 dogs, C6 to T1 in 1 dog, and C5 to T1 in 1 dog. The cutaneous branch of brachiocephalicus nerve was formed primarily by contributions from the C6 dorsal root. The cranial lateral cutaneous brachial nerve, a branch of the axillary nerve, was formed predominantly from C6 to C7. The median nerve received contributions primarily from C7, C8, and T1, and the communicating branch from the musculocutaneous to the median nerve contained fibers primarily from C7 and C8. The medial and lateral branches of the superficial branch of the radial nerve arose from C6, C7, C8, and T1, with the medial branch generally arising 1 segment craniad to the lateral. The palmar and dorsal branches of the ulnar nerve arose predominately from C8 and T1, and the caudal cutaneous antebrachial nerve of the ulnar arose predominately from T1 and T2.

Although there is a dose-response relationship between alcohol consumption and liver damage, less than one-third of alcoholics develop alcoholic liver disease (ALD). This individual susceptibility to the development of ALD may be explained by genetic and environmental factors. Of the genetic factors, female sex is clearly a significant risk factor, HLA status is probably important but further studies are needed, abnormalities in alcohol metabolism have not been shown to be of primary pathogenic importance and the plethora of immunological disturbances reported appear to be mere epiphenomena. Of the environmental factors, no consistent evidence attests to the significance of hepatitis B viral infection in the susceptibility to developing ALD.

Summary In 1974 and 1975 over 6000 secondary schoolchildren in an English county answered questionnaires on their smoking behaviour, social activities and attitudes towards various issues. An analysis of the 1974 replies of those children who were present in both years revealed certain factors which were associated with an increased risk of smoking in 1975. The most important factors were the extent of the children's involvement in social activities, the smoking behaviour of their parents, siblings and friends, and their own attitudes and beliefs about smoking. Analysis examining the relationships between these factors further helped to explain the development of smoking among schoolchildren.

Results from the Food and Drug Administration's Total Diet Study on the nutrient element content of fluid whole cow's milk are presented and compared with previously published values. Whole milk was collected and analyzed yearly from 1975 through 1985. Yearly and overall means were similar for all elements except iron and iodine. The iron content of milk was generally low, but several samples had high levels. The distribution of iodine in whole milk was quite wide (0.002 to 0.094 mg/100 gm). The iodine content of milk is affected by the level of iodine added to cattle feed and by the use of iodophor sanitizing solutions used by the dairy industry. Overall mean levels of the elements in milligrams per 100 gm whole milk were: sodium, 42; potassium, 134; calcium, 106; phosphorus, 83; magnesium, 9.8; iron, 0.07; zinc, 0.37; copper, 0.009; manganese, 0.004; iodine, 0.034; and selenium, 0.001. Coefficients of variation were high (67% to 117%) for iron, copper, manganese, selenium, and iodine but ranged from 18% to 26% for the other elements. An 8-fl oz serving of whole milk is an excellent source of iodine, calcium, phosphorus, and potassium. It also provides some sodium, magnesium, zinc, and selenium but is not a reliable source of iron, copper, or manganese.