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Bovine respiratory disease (BRD) is among the most important infectious disease facing the entire cattle industry. The economic consequences associated with BRD is significant and is one of the most challenging obstacles facing the profitably of cattle operations. Factors that contribute to respiratory diseases in cattle can be broken down into three different segments: viruses, bacteria, and stress. Due in large part to the structure of the U. S. cattle industry, there is no more critical time period cattle face in terms of the overall health and productivity than at weaning and as animals enter the feedlot. The objectives of this study were threefold: 1) to investigate the effects of BRD incidence and number of treatments on economically important performance and carcass traits. 2) to examine the effects lung lesion scores have on important production traits 3) to evaluate the genetic components associated with BRD in both pre-wean and feedlot cattle. In general, the results of this study agree with previous findings of the effect of BRD incidence on production traits, in which greater frequency of BRD treatment is associated with increasing effects on the traits of interest. In terms of lung lesion scores, the only significant differences in the traits of interest were observed when comparing cattle with and without active bronchial lymph nodes. The heritability for BRD incidences in pre-wean cattle was estimated at 0.12 ± 0.06 and 0.08 ± 0.05 for the number of BRD treatments in the current population. Heritability estimates were 0.07 ± 0.04 for BRD incidence and 0.05 ± 0.04 for the number of treatments in feedlot cattle. Though these estimates are low, genetic improvement may be possible through selection programs geared towards BRD resistance in pre-wean and feedlot cattle. Estimates of the genetic correlations between either health measure with hot carcass weight, rib-eye area

The objective of this study was to evaluate sire breed effect on mineral concentration in beef longissimus thoracis (LT) and investigate the correlations between beef mineral concentrations and carcass and palatability traits. Steer progeny (N=246) from the Germplasm Evaluation project-Cycle VIII were used in this study. In addition to carcass traits, LT was evaluated for mineral concentrations, Warner-Bratzler shear force, and palatability traits. A mixed linear model estimated breed effects on mineral concentrations. No significant sire breed (P≥0.43) or dam breed (P≥0.20) effects were identified for mineral concentrations. Pearson correlation coefficients were calculated among mineral concentrations, carcass, and sensory traits. Zinc concentration was positively correlated (P≤0.05) with total iron (r=0.14), heme iron (r=0.13), and magnesium (r=0.19). Significant (P0.05) correlations were identified between non-heme or heme iron and most traits in this study. Magnesium concentration was correlated with all carcass and palatability traits.

Presence of antibiotic residues in edible animal products is a human food safety concern. To address this potential problem, many governments sample edible tissues, such as muscle, to monitor for residues. Alternatively, antibiotic residue concentrations could be screened in blood which is readily available during carcass processing. To determine if blood concentrations are predictive of muscle concentrations, 252 market aged broilers were dosed with Oxytetracycline (OTC) in water at three doses: the maximum OTC approved dose for broilers (800 mg/gal) or five or ten times that dose. Blood and muscle samples were collected before initial dosing (0 hour, controls), during dosing at 1, 3, 6, 12, 24, 48, 96 or 144 hours and at 12, 24, 36, 48 or 60 hours after drug withdrawal. Concentrations in blood and muscle tissues followed similar time: concentration patterns, peaking 24 hours after initial dosing (396±9 vs. 557±37 ppb; 443±48 vs. 1846±58 ppb or 2447±67 vs. 3210±36 ppb for the 1, 5 or 10x doses in blood vs. muscle, respectively) and declined rapidly after withdrawal. These data suggest blood samples may be used to predict OTC concentrations in muscle as a screening procedure for OTC residues in poultry.

The primary objective of this study was to estimate variance components and heritability of bovine respiratory disease (BRD) incidence in beef calves before weaning and during the finishing phase. The second objective was to investigate the impact of BRD incidence and treatment frequency on performance and carcass traits. Bovine respiratory disease is the biggest and most costly health challenge facing the cattle industry. The 2 populations used consisted of 1,519 preweaned calves and 3,277 head of feedlot cattle. The incidence rate of BRD in preweaned calves was 11.39%, and among treated cattle, 82.1% were treated once, 13.9% were treated twice, and 4.0% were treated 3 times or more. The incidence of BRD (P = 0.35) and the number of treatments (P = 0.77) had no significant effect on weaning BW. Heritability estimates of the entire preweaned population for BRD resistance and number of treatments were 0.11 ± 0.06 and 0.08 ± 0.05, respectively. The genetic correlation estimates for BRD incidence with weaning BW and birth BW were low (−0.02 ± 0.32 and 0.07 ± 0.27, respectively). The same estimate for the number of BRD treatments with weaning BW and birth BW was 0.25 ± 0.35 and 0.30 ± 0.27, respectively. The observed BRD incidence rate for feedlot cattle was observed at 9.43%. Incidence of BRD significantly (P < 0.01) decreased overall and acclimation ADG by 0.06 ± 0.01 kg/d and 0.28 ± 0.03 kg/d, respectively. Carcass traits were also significantly (P < 0.05) affected by BRD incidence; untreated cattle had a 9.1 ± 1.7-kg heavier HCW. Results were similar in the analysis of treatment frequency. The heritability estimate of BRD incidence and the number of treatments were 0.07 ± 0.04 and 0.02 ± 0.03, respectively. Estimates of genetic correlations of BRD incidence with production traits were −0.63 ± 0.22 for acclimation ADG, −0.04 ± 0.23 for on-test ADG, −0.31 ± 0.21 for overall ADG, −0.39 ± 0.21 for final BW, −0.22 ± 0.22 for HCW, −0.03 ± 0.22 for LM area, 0.24 ± 0.25 for fat, and −0.43 ± 0.20 for marbling score. Similar results for the number of treatments and production traits were −1.00 ± 0.68 for acclimation ADG, −0.04 ± 0.39 for on-test ADG, −0.47 ± 0.41 for overall ADG, −0.66 ± 0.40 for final BW, −0.58 ± 0.45 for HCW, −0.12 ± 0.38 for LM area, 0.42 ± 0.50 for fat, and −0.32 ± 0.37 for marbling score. Because of the high economic cost associated with BRD incidence, even these modest estimates for heritability of BRD resistance should be considered for incorporation into beef cattle breeding programs.

The objective of this study was to in- vestigate the effects of bovine respiratory disease (BRD) complex on economically important production traits with the use of health records in combination with lung lesion scores obtained at slaughter. Records from 5,976 animals were used in this study from cattle that were managed in Midwestern feedlots. Average daily gain for 3 different feeding periods (acclimation, on-test, and overall test) along with final BW were evaluated as per- formance measures. Hot carcass weight, LM area, sub- cutaneous fat cover, and marbling score were collected at slaughter. All calves were monitored by experienced feedlot personnel and treated according to the specific health protocol of each feedlot. Incidence of BRD was observed at a rate of 8.17%, and lung lesions at slaugh- ter were present in 61.9% of cattle from a subpopula- tion (n = 1,665). From this group of cattle, the overall incidence of BRD, which was defined as cattle that had lung lesions, that were treated for BRD in the feedlot, or both, was 64.4%. Incidence of BRD in the feedlot de- creased ADG during both the acclimation period (0.37 ± 0.03 kg) and the overall test period (0.07 ± 0.01 kg). Incidence of BRD also had significant effects on HCW and marbling score with reduction of 8.16 ± 1.38 kg and 0.13 ± 0.04, respectively, in treated cattle. The ad- verse effects on production traits tended to increase as the number of treatments increased. Potential decrease in performance and carcass merit observed in this study were associated with a decline of $23.23, $30.15, and $54.01 in carcass value when comparing cattle never treated with cattle treated once, twice, or 3 or more times, respectively. The presence of lung lesions did not have a significant effect on any of the traits; however, there was an association between the presence of active bronchial lymph nodes and less productivity of feedlot cattle.

Regulatory monitoring for most antibiotic residues in edible poultry tissues is often accomplished with accurate, although expensive and technically demanding, chemical analytical techniques. The purpose of this study is to determine if a simple, inexpensive bioassay could detect fluoroquinolone (FQ) residues in chicken muscle above the FDA established tolerance (300 ppb) comparable to a liquid chromatography-fluorescencemass spectrometryn method. To produce incurred enrofloxacin (ENRO) tissues (where ENRO is incorporated into complex tissue matrices) for the method comparison, 40-d-old broilers (mixed sex) were orally dosed through drinking water for 3 d at the FDA-approved dose of ENRO (50 ppm). At the end of each day of the 3-d dosing period and for 3 d postdosing, birds were sacrificed and breast and thigh muscle collected and analyzed. Both methods were able to detect ENRO at and below the tolerance level in the muscle, with limits of detection of 26 ppb (bioassay), 0.1 ppb for ENRO, and 0.5 ppb for the ENRO metabolite, ciprofloxacin (liquid chromatography-fluorescence-mass spectrometryn). All samples that had violative levels of antibiotic were detected by the bioassay. These results support the use of this bioassay as a screening method for examining large numbers of samples for regulatory monitoring. Positive samples should then be examined by a more extensive method, such as liquid chromatography-fluorescence-mass spectrometryn, to provide confirmation of the analyte.

In order to examine the social conditions and effects of a broad usage of telecooperation technology in the future, such as the development of design proposals, PROVET (Projektgruppe Verfassungsverträgliche Technikgestaltung) developed the method of simulation studies. The paper describes the problem of prospective technology design for telecooperation, a method to handle it, the simulation studies and the methological background. It demonstrates three simulation studies, in administration of justice, about office dossiers and for a reachability management. It presents results, particularly about the psychological effects of the digital signature as a technical-organizational measure to guarantee obligations between the cooperation partners. The conclusion discusses this research approach in relation to others.

In 2005, the US Food and Drug Administration withdrew approval for use of enrofloxacin in poultry, thus effectively imposing zero tolerance for residues of this antibiotic in poultry. Conventional residue monitoring for most antibiotics, including enrofloxacin, involves removing poultry carcasses from the processing line and collecting muscle tissues for analysis. Because of the loss of valuable edible products and the difficulties and expense of sampling all the carcasses, only a small portion of carcasses are tested for violative residues. Unlike muscle tissue, blood is readily available from all birds at the beginning of processing and may be used to screen for illegal residues in all poultry carcasses. It is unknown, however, if enrofloxacin concentrations in blood are predictive of muscle concentrations. In an effort to evaluate this relationship, 156 broiler chickens, 5 wk of age, were dosed with either 25 or 50 µg/mL of enrofloxacin for 3 or 7 d, respectively, in the drinking water. Blood and muscle samples were collected at 0, 1, 3, 6, 12, and 24 h (n = 6 birds/group) during the first dosing day, every 48 h during the dosing period, and every 12 h during the withdrawal period for up to 60 h after withdrawal. Enrofloxacin residues were determined in all blood and tissue samples during the dosing periods and in most of the withdrawal period for both doses. These results support the potential to use blood to screen for illegal enrofloxacin residues in edible poultry tissues in an effort to protect the human food supply.

Summary The objective of this study was to assess the association of markers in the calpastatin and mu-calpain loci with iron in beef cattle muscle. The population consisted of 259 cross-bred steers from Beefmaster, Brangus, Bonsmara, Romosinuano, Hereford and Angus sires. Total iron and heme iron concentrations were measured. Markers in the calpastatin (referred to as CAST) and mu-calpain (referred to as CAPN4751) genes were used to assess their association with iron levels. The mean and standard error for iron and heme iron content in the population was 35.6 ± 1.3 μg and 27.1 ± 1.4 μg respectively. Significant associations (P

The objective of this study was to investigate the effects of bovine respiratory disease (BRD) complex on economically important production traits with the use of health records in combination with lung lesion scores obtained at slaughter. Records from 5,976 animals were used in this study from cattle that were managed in Midwestern feedlots. Average daily gain for 3 different feeding periods (acclimation, on-test, and overall test) along with final BW were evaluated as performance measures. Hot carcass weight, LM area, subcutaneous fat cover, and marbling score were collected at slaughter. All calves were monitored by experienced feedlot personnel and treated according to the specific health protocol of each feedlot. Incidence of BRD was observed at a rate of 8.17%, and lung lesions at slaughter were present in 61.9% of cattle from a subpopulation (n = 1,665). From this group of cattle, the overall incidence of BRD, which was defined as cattle that had lung lesions, that were treated for BRD in the feedlot, or both, was 64.4%. Incidence of BRD in the feedlot decreased ADG during both the acclimation period (0.37 +/- 0.03 kg) and the overall test period (0.07 +/- 0.01 kg). Incidence of BRD also had significant effects on HCW and marbling score with reduction of 8.16 +/- 1.38 kg and 0.13 +/- 0.04, respectively, in treated cattle. The adverse effects on production traits tended to increase as the number of treatments increased. Potential decrease in performance and carcass merit observed in this study were associated with a decline of $23.23, $30.15, and $54.01 in carcass value when comparing cattle never treated with cattle treated once, twice, or 3 or more times, respectively. The presence of lung lesions did not have a significant effect on any of the traits; however, there was an association between the presence of active bronchial lymph nodes and less productivity of feedlot cattle.

Materials and Methods Performance and health treatment records on 1714 Angus-sired calves fed at various feedlots over a three year period (2003-2005) were used in this analysis. Traits in this study were analyzed with general linear models to estimate significance and effects. We then evaluated the extent to which number of treatments for bovine respiratory disease influenced performance traits such as overall average daily gain (ADG), weight per day of age (WDA), age at harvest (AH), and carcass traits such as hot carcass weight (HCW), ribeye area (REA), ribeye area per 45.5 kg of carcass weight (REAcwt), calculated yield grade (YG), and marbling score (MS).

To rate specific chiropractic technique procedures used in the treatment of common low back conditions.A panel of chiropractors rated specific chiropractic technique procedures for their effectiveness in the treatment of common low back conditions, based on the quality of supporting evidence after systematic literature reviews and expert clinical opinion. Statements related to the rating process and clinical practice were then developed through a facilitated nominal consensus process.For most low back conditions presented in this study, the three procedures rated most effective were high-velocity, low- amplitude (HVLA) with no drop table (side posture), distraction technique, and HVLA prone with drop table assist. The three rated least effective were upper cervical technique, non-thrust reflex/low force, and lower extremity adjusting. The four conditions rated most amenable to chiropractic treatment were noncomplicated low back pain, sacroiliac joint dysfunction, posterior joint/subluxation, and low back pain with buttock or leg pain.The ratings for the effectiveness of chiropractic technique procedures for the treatment of common low back conditions are not equal. Those procedures rated highest are supported by the highest quality of literature. Much more evidence is necessary for chiropractors to understand which procedures maximally benefit patients for which conditions.

A multiresidue method was developed for the determination of fluoroquinolones in eggs. Extraction of eggs with ammoniacal acetonitrile was followed by liquid-liquid defatting, solvent evaporation, and redissolution in a small volume of buffer. The fluoroquinolones were further purified by on-line microdialysis, concentrated on a trace enrichment column, and separated by reversed-phase liquid chromatography with fluorescence detection. Norfloxacin (NOR), ciprofloxacin (CIP), and sarafloxacin (SAR) were extracted from fortified eggs over a range of 2-200 microg/kg, with recoveries of 65.7-78.9%, 65.6-77.1%, and 67.6-110%, respectively. Enrofloxacin (ENRO) was extracted over a range of 1-100 microg/kg, with recoveries of 71.5-86.7%, whereas desethylene ciprofloxacin (DCIP) and danofloxacin (DANO) were extracted over a range of 0.2-20 microg/kg, with recoveries of 68.7-90.7% and 76.0-93.8%, respectively. The limits of quantitation for the 6 fluoroquinolones were as follows: DCIP and DANO, 0.3 microg/kg; ENRO, 1 microg/kg; NOR and CIP, 2 microg/kg; and SAR, 3 microg/kg. Both SAR and ENRO incurred eggs were also successfully analyzed using this method.

The type 3 iodothyronine deiodinase (D3) is a selenoenzyme that inactivates thyroid hormones by removing a iodine from the 5-position of the tyrosyl ring. D3 is highly expressed in many tissues during the early stages of development, and its activity is regulated by selected growth factors and various hormones. To gain further insights into the structure, functional role, and regulation of this enzyme, we screened a mouse liver genomic library with a rat D3 complementary DNA probe and isolated a 12-kb clone coding for the Dio3. Restriction analysis followed by Southern blotting and nucleotide sequencing demonstrated that the Dio3 contains a single exon, 1853 bp in length, that encodes the entire length of the messenger RNA expressed in murine placenta and neonatal skin. Primer extension experiments identified two potential transcriptional start sites located 77 and 60 nt upstream of the ATG translational start codon. The region immediately 5' to the start sites contains consensus TATA, CAAT, and GC elements. Furthermore, a 526-nucleotide genomic fragment from this region was demonstrated to efficiently drive a luciferase reporter construct when transfected into COS-7, XTC-2, or XL-2 cells or into primary cultures of rat preadipocytes derived from neonatal brown fat. In conclusion, D3 transcripts in the placenta and skin are encoded by the Dio3 gene from a single exon whose expression is regulated by an upstream region that contains several consensus promoter elements. Further characterization of this gene will provide new insights into the factors regulating the unique pattern of D3 expression during development.

This study reviews the clinical distinctions between fibromyalgia (FM) and myofascial pain syndrome (MPS), which represent two separate and distinct soft-tissue syndromes. The major aim of this article is to clarify the terminology associated with these syndromes and clearly define the parameters of differential diagnosis and treatment.Pertinent articles in the chiropractic and medical literature are reviewed with an emphasis on the literature published from 1985-1994.Studies were selected that emphasized differential diagnosis of FM and MPS, as well as individual articles on either FM or MPS.The literature on fibromyalgia and myofascial pain syndromes has grown considerably since 1985. It is now clear that there are several important differences between FM and MPS. The most important criteria for differential diagnosis are the presence of tender points (TePs) and widespread, nonspecific, soft tissue pain in FM, compared with regional and characteristic referred pain patterns with discrete muscular trigger points (TrPs) and taut bands of skeletal muscle in MPS. The etiology of TePs is still unknown and it is uncertain which specific soft tissues are tender in FM patients. Myofascial TrPs are found within a taut band of skeletal muscle and have a characteristic "nodular" texture upon palpation. TrPs are thought to develop after trauma, overuse or prolonged spasm of muscles. Local treatment applied to TePs is ineffective, yet specific treatment of TrPs is often dramatically effective.FM and MPS are two different clinical conditions that require different treatment plans. FM is a systemic disease process, apparently caused by dysfunction of the limbic system and/or neuroendocrine axis. It often requires a multidisciplinary treatment approach including psychotherapy, low dose antidepressant medication and a moderate exercise program. MPS is a condition that arises from the referred pain and muscle dysfunction caused by TrPs, which often respond to manual treatment methods such as ischemic compression and various specific stretching techniques. Both of these conditions are seen routinely in chiropractic offices; therefore, it is important for field practitioners to understand these distinctions.

Venoms from five Old World and two New World scorpions were tested for their ability to block various K+ channels in rat brain synaptosomes. A 86Rb efflux kinetic assay was used to identify three types of K+ channels, Ca(2+)-independent, voltage-gated, inactivating (A-type) and noninactivating (delayed rectifier) K+ channels and Ca(2+)-activated K+ channels [J. Physiol. (Lond.) 361:419-440, 441-457 (1985)]. The venoms from the Old World scorpions all blocked the A-type K+ channel but not the delayed rectifier K+ channel; only venom from the Israeli scorpion, Leiurus quinqestriatus hebraeus (Lqh), blocked the Ca(2+)-activated K+ channel. In contrast, venoms from the two New World scorpions selectively blocked the delayed rectifier K+ channel. Water-soluble components from Lqh venom from the Brazillian scorpion, Tityus serrulatus (Ts), were separated by ion exchange high performance liquid chromatography (HPLC). Seven components that blocked synaptosome K+ channels were isolated from Lqh venom by ion exchange HPLC. All seven components blocked the A-type K+ channel; the five most potent toxins had IC50 values of 18-40 nM. Two of the components from Lqh venom (one identified as charybdotoxin and the other denoted as Lqk4) also blocked a Ca(2+)-activated K+ channel (IC50 = 15 and 60 nM for charybdotoxin and Lqk4, respectively). Five K+ channel-blocking components were isolated from the Ts venom; all five blocked the delayed rectifier channel selectively, and the two most potent components had IC50 values of 8 and 30 nM. Several of the more potent Lqh and Ts toxins were purified to near-homogeneity by reverse phase HPLC. These toxins should be useful as ligands for K+ channel purification, for elucidation of K+ channel structure, and for studies of K+ channel function.

Senescence and other developmental processes are often or perhaps always under correlative control [17]. These controls appear to be mediated mainly by hormones as opposed to nutrient fluxes or other influences [6]. Determining the correlative controls is an important first step in understanding the hormonal controls of senescence, and together these will provide “handles” for analyzing the biochemistry of senescence.

A temperature-dependent small-angle x-ray scattering and electron microscopic study on a sample of low-density polyethylene affords a determination of the structure changes in a heating and cooling cycle and suggests a new model of partial crystallization and melting. The analysis of SAXS data is based upon some general properties of the electron-density correlation function. Electron micrographs are obtained from stained sections γ irradiated at elevated temperatures and are analyzed quantitatively by statistical means. According to the model proposed here the thickness distribution in the amorphous layers, rather than that of the crystalline regions, is the essential factor governing the crystallization and melting behavior. The temperature-dependent changes in this thickness distribution provide a natural explanation for the large reversible changes in long-spacing.

A discussion of the general properties of the one-dimensional electron density correlation function K(z) of a partially crystalline polymer with lamellar structure shows that application of a graphical extrapolation procedure permits direct determination of the crystallinity, the specific inner surface, and the electron density difference ηc − ηa. The procedure is based upon the occurrence of a straight section in the “self-correlation” range of K(z). Curved and nonparallel lamellae do not invalidate the concept. In the case of heterogeneous samples composed of partially crystalline and totally amorphous regions, some of the parameters of the experimentally obtained correlation function, as for example the invariant K(0), are affected and may lose their definiteness. Use of the method is demonstrated in a detailed discussion of the correlation functions measured for a sample of lowdensity polyethylene at 25 and 100°C.

Resistance to abrupt and gradual cold shock was determined in bioassays with pumpkinseed (Lepomis gibbosus), rainbow trout (Salmo gairdneri), and a northwestern crayfish (Pacifastacus leniusculus) acclimated to higher temperatures at 5 C increments. Test criteria were median tolerance limits (TLm) for 96-h exposures after abrupt cold shock, and 50% loss of equilibrium (LE50) for decline rates of 18, 15, 10, 5, and 1 C/h during gradual cold shock. Cold resistance depended on original acclimation temperature (AT) and varied among species under both test conditions in the order: pumpkinseed < rainbow trout < crayfish. The lower TLm limit for pumpkinseed was 12.3 C at 30 C AT, 9.6 C at 25 C AT, 4.5 C at 20 C AT, and 2.7 C at 15 C AT. Rainbow trout at 20, 15 and 10 C AT survived abrupt exposures to cold down to 3.3, 1.4 and 0.5 C, respectively. Crayfish at 25, 20 and 15 C AT survived exposures down to 2.5, 0.4 and 0.0 C, respectively. TLm values were slightly above LE50 values for both fish species bu...

Between 1957 and 1972, 384 patients with bladder cancers were treated initially with megavoltage radiation therapy. Actuarial five-year survival ranged from 35 to 42% for Stages A and B1 tumors, and was 35, 22 and 7%, respectively, for Stages B2, C and D carcinomas. Approximately 30-40% of deeply invasive tumors confined to the bladder can be controlled with radiation therapy alone, directed solely to the bladder itself.

1. Mimosa pudica L. pinnae close in darkness when phytochrome is predominantly in the far-red-absorbing form (Pfr) and remain open when Pfr is low [6]. The leaflets remain open, however, in normal light periods irrespective of the form of phytochrome. Pinnae, after closing in darkness, regularly reopen in light. 2. An action spectrum for the opening response shows maxima for effectiveness near 710 and 480 nm. This action spectrum is similar to that for a high-energy response affecting morphogenesis in many plants. 3. Dropping of the petiole of M. pudica can be photostimulated by irradiation of the primary pulvinus after holding the plants in darkness [4]. 4. The photostimulation of the primary pulvinus is effective only at wavelengths less than 520 nm. Wave bands in the region of 400 to 470 nm are about equally effective. 5. These photoresponses of M. pudica are related to current discussion about the nature of the high-energy and phytochrome photomorphogenic reactions.

Turnip seedlings (Brassica rapa L.) irradiated for 24 hours with radiation at 720 nanometers synthesize chlorophyll a and anthocyanin. Antimycin A and 2,4-dinitrophenol, which are known to reduce cyclic photophosphorylation, also reduce anthocyanin synthesis. Noncyclic photophosphorylation is inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea and o-phenanthroline. These compounds promote cyclic photophosphorylation and anthocyanin synthesis. On the basis of these findings it is suggested that the photomorphogenic response of anthocyanin synthesis in turnip seedlings arises in part through photosynthetic activity.Phytochrome involvement in turnip seedling photomorphogenesis is evidenced by the photoreversibility of anthocyanin synthesis in response to 5-minute irradiations with red or far red light. The inhibition of anthocyanin synthesis by 2,4-dinitrophenol does not arise from a destruction of phytochrome photoreversibility.It is suggested that plant photomorphogenic responses to prolonged far red irradiations arise through the photochemical activation of at least two pigment systems; namely, the photosynthetic pigments and phytochrome.

Charybdotoxin (ChTX), a 4.3 kDa polypeptide toxin from the venom of the scorpion Leiurus quinquestriatus, blocks both a Ca-activated K channel (IC50 approximately 15 nM) and a Ca-independent voltage-gated K channel (IC50 approximately 40 nM) in rat brain synaptosomes. These results indicate that in this preparation ChTX is not specific for the Ca-activated K channel and suggest that there may be structural homology among the toxin-binding sites on various types of K channels.

Small plastic spawning baskets served successfully as spawning sites for the laboratory reared brook trout. Five of the six pairs of 1-yr-old trout spawned with normal egg production in four pairs. The temperature was maintained at 9.4 to 15.4/sup 0/C for optimum growth. Fungus disease, especially in the males, was the principal problem encountered during the spawning attempt. (RAF)

The purpose of the investigation was to explore the validity of using timed distance runs as predictorr of cardiorespiratory fitness in young untrained children. Maximal oxygen consumption and performance in runs of 549, 1207, and 1609 meters (600 yards, 3/4 mile, and 1 mile) were compared in 38 children eight years of age. Males were found to exceed females on Vo2max and possessed significantly faster times in the 1207 and 1609 meter runs. The females exhibited greater six-site skinfold totals. The 1609 meter run proved to be the best predictor of Vo2max (ml/kg) in males. However, none of the three distances was acceptable for females.

Groups of Eastern brook trout, Salvelinus fontinalis, were acclimated to four temperatures (7, 10, 15, or 20/sup 0/C) for two weeks; however, due to disease problems the 20/sup 0/C group was discarded after bioassay number 2. Separate subsamples of each acclimation group were exposed to a range of chlorine values at three temperatures (10, 15, 20/sup 0/C). There was no significant difference between the 96-hr mortality values at 10 or 15/sup 0/C regardless of previous acclimation temperature. However, in fish exposed to 20/sup 0/C test temperature, all 96-hr LC50 values were significantly less than at the lower test temperatures. The lower 96-hr LC50 values at the 20/sup 0/C test temperature were also independent of acclimation temperature. Differences were also observed between early mortality and 96 hr mortality. Groups that had experienced the greater temperature change from acclimation, experienced the higher mortality, regardless of whether the change was an increase or decrease. (ND)

The purpose of the investigation was to explore the validity of using timed distance runs as predictors of cardiorespiratory fitness in first, second and third grade children. Maximal oxygen uptake (Vo2 max), determined via the open-circut method during treadmill running, and performance on runs of 800, 1200 and 1600 meters were compared for 83 children. Males were found to exceed females on Vo2 max and possessed significantly faster times on all the distances run. The 1600-meter run proved to be the best predictor of Vo2 max (ml/kg) in both sexes. Test-retest reliability of the 1600-meter run was checked with 120 students and found to range from +.824 for first grade females to + .918 for third grade males. Normative values for first, second, and third grade students were calculated from data collected on 1440 elementary students. All subjects studied had previously received instruction and practice on the phenomenon of paced distance running.

Evidence is advanced for a network of three photoreactions and five dark reactions in control of plant growth and development by phytochrome.