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Context: A great body of evidence is available on the in vitro efficacy of white-rot fungi (WRF) to degrade lignin in fibre-rich biomass (e.g. wheat straw, wood chips and rice straw (RS)) and improve the biomass' nutritive value for ruminants. Aims: Determining the impact of incubation temperature of three WRF to improve the nutritional value of rice straw. Methods: Growth of Ceriporiopsis subvermispora , Lentinula edodes and Pleurotus eryngii on RS for 26 days at the following six temperature regimes: continuous at 24°C, 30°C, 35°C and 40°C, and 3 days at 35°C and 40°C, with subsequent days at 24°C. In a follow-up experiment, improvement in fermentability in buffered rumen fluid of RS treated by the three WRF at 24°C and 30°C for up to 8 weeks was investigated. Key results: All three fungi grew at temperatures up to 35°C, with no growth observed at 40°C, with C. subvermispora being more temperature sensitive. There were significant differences in cellulose, hemicellulose and lignin degradation of RS at 24°C and 30°C, with C. subvermispora degrading 69% and 90% of the hemicellulose and lignin respectively at 30°C, greater than at 24°C (55% and 80% respectively). For L. edodes , there were significant differences in cellulose degradation between 24°C and 30°C, with 12% more degradation at 30°C, but not for hemicellulose and lignin. In vitro gas production showed no significant differences between the two incubation temperatures for either of the two fungi. Pleurotus eryngii treatment did not show any improvement in terms of in vitro gas production. Conclusions: Treatment of RS with L. edodes and C. subvermispora , but not P. eryngii , is robust and temperature changes will not have a major impact on their efficacy as long as the temperature remains below 30°C. Implications: Temperature during the incubation of WRF with rice straw needs to be below 30°C for this biotechnology to be applied in practice. White-rot fungus technology can revolutionise the utilisation of rice straw, because it enhances its quality by breaking down rigid components and boosting nutritional value. Investigating the temperature tolerance of these fungi is crucial for the practical application process, ensuring their effectiveness in diverse enviromental conditions and promoting their use in livestock feed. Unlocking their potential can increase the utility of this abundant by-product, contributing to environmental sustainability and agricultural productivity. This article belongs to the Collection Sustainable Animal Agriculture for Developing Countries 2023. [ABSTRACT FROM AUTHOR]

This study was conducted to identify the nutritive and anti-nutritive composition, in situ rumen degradability, and the kinetics of in vitro gas production of Persian oak (Quercus persica) leaves harvested at three growth stages during the spring season. A tannin bioassay was also performed using polyethylene glycol (PEG 6000) as a tannin-complexing agent in a gas production test. Leaves were harvested in monthly intervals in spring, starting on April when leaves were at the early vegetative stage, and then May and June. As the leaf maturity progressed, crude protein decreased but total phenols, total tannins, and hydrolysable tannins increased. Condensed tannin concentration was not affected by maturity stage (Average=13.0 mg leucocyanidin equivalent/g dry matter (DM)). As leaf maturity increased, the rapidly degradable A fraction of DM increased. In vitro gas production, metabolizable energy, in vitro DM degradability, ruminal NH3-N, and short-chain fatty acid concentrations were greatest in leaves harvested at the early vegetative stage (April) compared with other months. Application of PEG increased in vitro gas production, metabolizable energy, in vitro DM degradability, and NH3-N and short-chain fatty acid production in the rumen fluid compared with no addition of PEG. Overall, oak leaves harvested at the early vegetative stage appeared to be a good source of forage for ruminants. However, as leaf maturity increased, ruminal fermentability de)creased, which was improved with PEG addition. [ABSTRACT FROM AUTHOR]

Summary: The relationship between in vitro rumen CH4 production of grass silages, using the gas production technique, and in vivo data obtained with the same cows and rations in respiration chambers was investigated. Silages were made from grass harvested in 2013 on May 6th, May 25th, July 1st and July 8th. The grass silages were used to formulate four different rations which were fed to 24 cows in early and late lactation, resulting in a slightly different dry matter intake (DMI; 16.5 kg/day vs. 15.4 kg/day). The experimental rations consisted of 70% grass silage, 10% maize silage, and 20% concentrates on a dry matter basis. Cows were adapted to the rations for 17 days before rumen fluid was collected via oesophageal tubing, and in vitro gas and CH4 production were analysed. In vitro total gas and CH4 production of the (ensiled) grass expressed as ml/g OM decreased with advancing maturity of the grass. The in vitro CH4 production after 48 hr of incubation expressed in ml/g OM did not correlate with the in vivo CH4 production expressed in g/kg organic matter intake or g/kg DMI (R2 = .00–.18, p ≥ .287). The differences in CH4 emission per unit of intake observed in vivo were rather small between the different rations, which also contributed to the observed poor relationship. Utilizing stepwise multiple regression improved the correlation only slightly. In vitro gas and CH4 production varied based on whether donor cows were previously adapted to the respective ration or not, suggesting that careful adaption to the experimental diet should be envisaged in in vitro gas and CH4 production experiments. [ABSTRACT FROM AUTHOR]

Abstract: Aim: In this study, the biological variation for improvement of the nutritive value of wheat straw by 12 Ceriporiopsis subvermispora, 10 Pleurotus eryngii and 10 Lentinula edodes strains was assessed. Screening of the best performing strains within each species was made based on the in vitro degradability of fungal‐treated wheat straw. Methods and Results: Wheat straw was inoculated with each strain for 7 weeks of solid state fermentation. Weekly samples were evaluated for in vitro gas production (IVGP) in buffered rumen fluid for 72 h. Out of the 32 fungal strains studied, 17 strains showed a significantly higher (P < 0·05) IVGP compared to the control after 7 weeks (227·7 ml g−1 OM). The three best Ceriporiopsis subvermispora strains showed a mean IVGP of 297·0 ml g−1 OM, while the three best P. eryngii and L. edodes strains showed a mean IVGP of 257·8 and 291·5 ml g−1 OM, respectively. Conclusion: Ceriporiopsis subvermispora strains show an overall high potential to improve the ruminal degradability of wheat straw, followed by L. edodes and P. eryngii strains. Significance and Impact of the Study: Large variation exists within and among different fungal species in the valorization of wheat straw, which offers opportunities to improve the fungal genotype by breeding. [ABSTRACT FROM AUTHOR]

Experiments were conducted to determine the effect of lime pre-treatment on the chemical composition and in vitro rumen degradability of date palm leaves (DPL). Lime pre-treatments, with or without oxygen supply, were applied for 1, 2 and 3 weeks at 25 and 40 °C. Lime was neutralized by the Calcium-Capturing-by-Carbonation process. Delignification and in vitro rumen gas production were significantly influenced by duration, temperature and oxygen. At 40 °C, oxygen presence stimulated more delignification and subsequently increased in vitro rumen degradability. Lime pre-treatment with 0·2 g calcium hydroxide (Ca(OH)2)/g dry biomass for 3 weeks at 40 °C in the presence of oxygen resulted in a 3-fold increase in gas production after 24 h of incubation, compared with untreated biomass. Lime treatment of DPL with aeration resulted in higher lignin removal and subsequent rumen degradability than without aeration. A techno-economic analysis is needed to select the most efficient and economically feasible pre-treatment procedure. [ABSTRACT FROM PUBLISHER]

The aim of this study was to quantify the fatty acid (FA) content and composition of forages commonly fed to dairy animals in the tropics. Twelve forage species, namely, Trifolium alexandrinum, Cichorium intybus, Hordeum vulgare L., Medicago sativa, Avena sativa, Pennisetum purpureum, Setaria anceps, Sorghum almum, Panicum maximum, Rumex nepalensis, Panicum coloratum and Panicum antidotale were evaluated. Each forage species was grown in four replicate plots under standard agronomic conditions, and sampled at early, normal and late stages of maturity. The result of the present study showed that the chemical composition, dry matter digestibility and FA contents varied (P < 0.001) among forage species and harvest maturity. Linolenic acid (C18:3n-3), palmitic acid (C16:0) and linoleic acid (C18:2n-6) were the predominant FAs with an average content of 8.65, 3.61 and 2.38 g/kg dry matter (DM), contributing on average to 53%, 22% and 14% of the total measured FAs, respectively. Among the individual FAs, C18:3n-3 had the largest variation ranging from 4.26 to 17.43 g/kg DM at first harvest. The content of C16:0, C18:2n-6 and C18:3n-3 decreased (P < 0.001) with maturity, with the largest decrease being observed in C18:3n-3. This study highlights that harvest management is an important tool to manipulate the FA contents and composition within a forage species. [ABSTRACT FROM AUTHOR]

The high content of lignin in cell walls is the major limiting factor in the digestion and utilisation of cereal crop residues by ruminants. The aim of this study was to evaluate the effectiveness of the white rot fungus, Pleurotus ostreatus (P. ostreatus), to degrade lignin and to enhance the rumen degradability of maize stover, rice straw, wheat straw and their mixture in equal proportion on a dry-matter (DM) basis. Four samples of each substrate were incubated aerobically in triplicate with P. ostreatus for 0 (Control), 21, 28 and 35 days under solid-state conditions (temperature, 24°C; humidity, 70 ± 5%). The changes in chemical composition, DM and nutrient losses, and rumen fermentation characteristics using in vitro DM digestibility (DMD) and the in vitro gas-production (GP) technique were measured. The results showed that incubation with P. ostreatus decreased (P < 0.001) the contents of neutral detergent fibre and lignin with a concomitant increase (P < 0.001) in the contents of ash and crude protein. The losses of nutrients differed (P < 0.001) among the straw types, with rice straw and maize stover showing the largest (P < 0.05) lignin degradation compared to wheat and mixed straws. The DMD and 72-h cumulative GP increased (P < 0.001) consistently with increasing fungal incubation period and for all substrates the highest values of DMD and GP were measured after 35 days of incubation with P. ostreatus. The lignin degradation was strongly associated with hemicellulose degradation (r = 0.71) across the various straws. Results of the present study demonstrated that incubation of low-quality crop residues with P. ostreatus under solid-state conditions upgrades their feeding value by reducing the content of lignin and increasing the content of crude protein and ruminal degradation. [ABSTRACT FROM AUTHOR]

Several in situ studies have been conducted on maize silages to determine the effect of individual factors such as maturity stage, chop length and ensiling of maize crop on the rumen degradation but the information on the relationship between chemical composition and in situ rumen degradation characteristics remains scarce. The objectives of this study were to determine and describe relationships between the chemical composition and the rumen degradation characteristics of dry matter (DM), organic matter (OM), CP, starch and aNDFom (NDF assayed with a heat stable amylase and expressed exclusive of residual ash) of maize silages. In all, 75 maize silage samples were selected, with a broad range in chemical composition and quality parameters. The samples were incubated in the rumen for 2, 4, 8, 16, 32, 72 and 336 h, using the nylon bag technique. Large range was found in the rumen degradable fractions of DM, OM, CP, starch and aNDFom because of the broad range in chemical composition and quality parameters. The new database with in situ rumen degradation characteristics of DM, OM, CP, starch and aNDFom of the maize silages was obtained under uniform experimental conditions; same cows, same incubation protocol and same chemical analysis procedures. Regression equations were developed with significant predictors (P<0.05) describing moderate and weak relationships between the chemical composition and the washout fraction, rumen undegradable fraction, potentially rumen degradable fraction, fractional degradation rate and effective rumen degradable fraction of DM, OM, CP, starch and aNDFom. [ABSTRACT FROM PUBLISHER]

This study investigated the effect of chilling and freezing (for 24 h) canine feces on in vitro gas production kinetics and fermentation end product profiles from carbohydrate-rich (in vitro run 1) and protein-rich (in vitro run 2) substrates. Feces were collected from 3 adult retriever-type dogs fed a canned diet for at least 2 wk. Each fecal sample was divided into 3 portions: 1 portion was used immediately as an inoculum (fresh) and the other 2 portions were used after either chilling to 5°C for 30 min and storage in crushed ice for 23.5 h (chilling) or freezing to -20°C for 30 min and storage in a prefrozen (-20°C) container for 23.5 h (freezing). The medium solution for run 1 contained N whereas that for run 2 was N free. Substrates included fructooligosaccharide (FOS), sugar beet pulp, and wheat middlings in run 1 and soybean meal, poultry meat meal, and feather meal in run 2. Gas production kinetics were calculated from cumulative gas production data measured for 72 h. After incubation, fermentation liquids were analyzed for short-chain fatty acids, NH3, and aromatic compounds. For both in vitro runs, chilling feces did not affect gas production kinetics and end product profiles of substrates compared with inocula from fresh feces. Freezing feces decreased the maximum rate of gas production in phase 2 for FOS (P < 0.001) and across substrates increased gas produced (P < 0.005) and time of maximum gas production in phase 2 (P < 0.001). Furthermore, compared with fresh fecal inocula, inocula from frozen feces resulted in increased overall indole concentrations in run 1 (P = 0.006) and indole concentrations from soybean meal and poultry meat meal in run 2 (P < 0.001). In run 2, phenol concentrations were greater (P = 0.015) for frozen feces than for fresh feces (P = 0.015). In conclusion, freezing canine feces for 24 h slightly altered fermentative characteristics of fecal inoculum whereas chilling feces in crushed ice for 24 h maintained fermentative characteristics. Chilling feces in crushed ice is a practical method to preserve feces during transport between laboratories within 24 h for in vitro fermentation studies evaluating dietary ingredients. [ABSTRACT FROM AUTHOR]

One of the challenging features of studying model Hamiltonians with cold atoms in optical lattices is the presence of spatial inhomogeneities induced by the confining potential, which results in the coexistence of different phases. This paper presents quantum Monte Carlo results comparing methods for confining fermions in two dimensions, including conventional diagonal confinement, a recently proposed "off-diagonal confinement", as well as a trap which produces uniform density in the lattice. At constant entropy and for currently accessible temperatures, we show that ( 1 ) diagonal confinement results in the strongest signature of magnetic order, primarily because of its judicious use of entropy sinks at the trap edge and that (2) for d-wave pairing, a trap with uniform density is optimal and can be effectively implemented via off-diagonal confinement. This feature is important to any prospective search for superconductivity in optical lattices. [ABSTRACT FROM AUTHOR]

SUMMARY: In the current Dutch protein evaluation system (the DVE/OEB1991 system), two characteristics are calculated for each feed: true protein digested in the intestine (DVE) and the rumen degradable protein balance (OEB). Of these, DVE represents the protein value of a feed, while OEB is the difference between the potential microbial protein synthesis (MPS) on the basis of available rumen degradable protein and that on the basis of available rumen degradable energy. DVE can be separated into three components: (i) feed crude protein undegraded in the rumen but digested in the small intestine, (ii) microbial true protein synthesized in the rumen and digested in the small intestine, and (iii) endogenous protein lost in the digestive processes. Based on new research findings, the DVE/OEB1991 system has recently been updated to the DVE/OEB2010 system. More detail and differentiation is included concerning the representation of chemical components in feed, the rumen degradation characteristics of these components, the efficiency of MPS and the fractional passage rates. For each chemical component, the soluble, washout, potentially degradable and truly non-degradable fractions are defined with separate fractional degradation rates. Similarly, fractional passage rates for each of these fractions were identified and partly expressed as a function of fractional degradation rate. Efficiency of MPS is related to the various fractions of the chemical components and their associated fractional passage rates. Only minor changes were made with respect to the amount of DVE required for maintenance and production purposes of the animal. Differences from other current protein evaluation systems, viz. the Cornell Net Carbohydrate and Protein system and the Feed into Milk system, are discussed. [ABSTRACT FROM AUTHOR]

Experiments on cold atom systems in which a lattice potential is ramped up on a confined cloud have raised intriguing questions about how the temperature varies along isentropic curves, and how these curves intersect features in the phase diagram. In this paper, we study the isentropic curves of two models of magnetic phase transitions-the classical Blume-Capel model (BCM) and the Fermi Hubbard model (FHM). Both mean field theory and Monte Carlo methods are used. The isentropic curves of the BCM generally run parallel to the phase boundary in the Ising regime of low vacancy density, but intersect the phase boundary when the magnetic transition is mainly driven by a proliferation of vacancies. Adiabatic heating occurs in moving away from the phase boundary. The isentropes of the half-filled FHM have a relatively simple structure, running parallel to the temperature axis in the paramagnetic phase, and then curving upward as the antiferromagnetic transition occurs. However, in the doped case, where two magnetic phase boundaries are crossed, the isentrope topology is considerably more complex. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the intake and digestive physiology of mature ewes of two breeds − Ile-de-France (mature weight: 75-80 kg) and Churra-da-Terra-Quente (CTQ; mature weight: 45-50 kg) − and evaluate the effects of ambient temperature and protein supplementation in the comparison. The temperature (25 °C vs. 11 °C) and soybean meal supplementation (150 g/kg of ingested hay on dry matter basis vs. unsupplemented control) were evaluated in 48 adult ewes of two breeds fed hay ad libitum and at a restricted level of intake. The intake, digestibility, rumen pH and NH3-N, rumen outflow rates, faeces particle size and thyroid hormones levels were measured. These hormones can be related with gastrointestinal motility, thus explaining rumen outflow rate patterns. Dry matter intake per kg of body weight was higher in CTQ ewes (p < 0.05). This breed also exhibited lower organic matter and neutral detergent fibre digestibility (p < 0.001) and higher solid (p < 0.001) and liquid (p < 0.01) rumen outflow rates irrespective of intake level, supplementation or temperature. Rumen pH remained above 6.6 in all treatments. NH3-N rumen content was similar (p > 0.05) when breeds were fed only hay. There was no breed effect (p > 0.05) on faeces particle size. Triiodothyronine was not affected (p > 0.05) by breed and thyroxine was higher (p < 0.10) in the CTQ breed but only at the lower temperatures (breed × temperature, p < 0.05). Ile-de-France sheep showed a lack of adaptation to lower temperatures. This study suggests that the native CTQ breed fulfils its metabolic needs by having a higher intake and inherits faster flow through the gastrointestinal tract, as a result, its digestive ability is diminished. [ABSTRACT FROM AUTHOR]

An in vivo experiment was performed to determine the effect of level of maize starch in the diet on digestion and site of digestion of organic matter, starch and neutral detergent fibre (NDF). In a repeated change-over design experiment, three cows fitted with a rumen cannula and T-piece cannulae in duodenum and ileum received a low-starch (12% of ration dry matter) and a high-starch (33% of ration dry matter) diet. Starch level was increased by exchanging dried sugar beet pulp by ground maize. After a 2-week adaptation period, feed intake, rumen fermentation parameters ( in vivo and in situ), intestinal flows, faecal excretion of organic matter, starch and NDF were estimated. When the high-starch diet was fed, dry matter intake was higher (19.0 kg/day vs. 17.8 kg/day), and total tract digestibility of organic matter, starch and NDF was lower when the low-starch diet was fed. Maize starch concentration had no significant effect on rumen pH and volatile fatty acid concentration nor on the site of digestion of organic matter and starch and rate of passage of ytterbium-labelled forage. On the high-starch diet, an extra 1.3 kg of maize starch was supplied at the duodenum in relation to the low-starch diet, but only an extra 0.3 kg of starch was digested in the small intestine. Digestion of NDF was only apparent in the rumen and was lower on the high-starch diet than on the low-starch diet, mainly attributed to the reduction in sugar beet pulp in the high-starch diet. It was concluded that without the correction for the reduction in NDF digestion in the rumen, the extra supply of glucogenic (glucose and propionic acid) and ketogenic nutrients (acetic and butyric acid) by supplemented starch will be overestimated. The mechanisms responsible for these effects need to be addressed in feed evaluation. [ABSTRACT FROM AUTHOR]

Experiments were conducted to investigate the influence of the adaptation of rumen micro-organisms on the degradation of native potato starch (PS) in the rumen. Cows were fed with rations used for gas production (GP) analysis (dry cows, 1.6% starch) and for the nylon bag (NB) technique (lactating cows, 23% starch, mainly maize starch) and a ration containing 19% native PS (lactating cows). Fermentation characteristics of 13 samples were investigated with the GP technique using rumen fluid from cows fed each of the three rations. The same samples were investigated with the NB technique in the cows obtaining the NB ration and the PS ration. The results showed that the rate of GP was influenced by the source of the rumen fluid. The fermentation rate of PS was considerably enhanced by using rumen fluid adapted to the fermentation of native PS instead of using the other rumen fluids. Incubating in cows fed the PS ration, the rate of PS degradation determined with the NB technique, was higher compared with cows fed other rations. Using the PS ration the observed lag period for PS was shorter. The results show a clear influence of ration on the degradation characteristics of starch, determined with both the GP technique and the NB technique. However, these changes in behaviour did not explain observed differences in amounts of rumen escape PS measured in vivo in animal experiments and in situ, using the NB technique. [ABSTRACT FROM AUTHOR]

Problem/Condition: Survivors of collapsed or damaged buildings from the attack on the World Trade Center (WTC) were among those most exposed to injury hazards, air pollution, and traumatic events.Reporting Period: This report summarizes data from health outcomes collected during interviews conducted from September 5, 2003, to the close of the World Trade Center Health Registry (WTCHR) enrollment on November 20, 2004.Description of System: WTCHR will be used to monitor periodically the mental and physical health of 71,437 enrollees for 20 years. The analysis is limited to 8,418 adult survivors of collapsed buildings (n = 5,095) and buildings with major or moderate damage (n = 3,323), excluding those who were involved in rescue and recovery.Results: A total of 62.4% of survivors of collapsed or damaged buildings were caught in the dust and debris cloud that resulted from the collapse of the WTC towers, and 63.8% experienced three or more potentially psychologically traumatizing events. Injuries were common (43.6%), but few survivors reported injuries that would have required extensive treatment. More than half (56.6%) of survivors reported experiencing new or worsening respiratory symptoms after the attacks, 23.9% had heartburn/reflux, and 21.0% had severe headaches. At the time of the interview, 10.7% of building survivors screened positive for serious psychological distress (SPD) using the K6 instrument. After multiple adjustments, data indicated that survivors caught in the dust and debris cloud were more likely to report any injuries (adjusted odds ratio [AOR] = 3.9; p

Discusses several representative cases and investigations into the cases of atypical reactions associated with heroin use conducted by state and local health and law enforcement and the U.S. Centers for Disease Control and Prevention (CDC) from January 28 to April 17, 2005. Total number of atypical reaction cases reported to the New Jersey Poison Information and Education System; Details of clinical findings; Action taken by CDC to facilitate uniform reporting of heroin adulterated with clenbuterol.

Prediction of the supply of glycogenic precursors to dairy cows and the site of degradation of wheat, maize and potato starch (PS) were determined in anin vivoexperiment and the results were compared with data obtained from experiments involvingin situnylon bag andin vitrogas production techniques. In a Latin square design experiment four lactating dairy cows fitted with a rumen cannula and T-piece cannulae in the duodenum and terminal ileum, received either a low-starch control diet or diets in which sugar beet pulp in the concentrate mixture had been replaced by wheat, maize or PS. Starch from the different sources was almost completely degraded in the total gastrointestinal tract. For all starches, the rumen was the main site of degradationin vivo. No digestion of PS in the small intestine was observed.In situresults suggested that 14% of wheat starch (WS), 47% of maize starch and 34% of PS escaped rumen fermentation. According to the gas production technique WS ferments quickest and potato slowest. PS had a low degradability during the first 8 (gas production) to 11 (in situ) h. However, according to bothin vitroandin vivomeasurements rumen degradability of PS was high. The results suggest thatin situandin vitrotechniques should be performed in animals that have adapted to starch source to provide a more accurate simulation of thein vivosituation. [ABSTRACT FROM AUTHOR]

The optimal combinations of temperature in the range of 0 to 20°C and duration (1 to 14 days) of imbibition for the induction of germination of Arabidopsis thaliana (L.) Heynh., ecotype "Landsberg-erecta", by red light were investigated. At 2°C, 10 days of imbibition are needed for loss of dormancy, whereas at higher temperatures, e.g. 15°C, it is already lost after I or 2 days. It is proposed that the development of light-inducible germination is governed by two temperature-dependent processes. the loss of primary or innate dormancy and the simultaneous induction of secondary dormancy. Data are discussed in terms of the availability of phytochrome. the availability of an unknown factor X and changes in sensitivity of the process of germination induction by the far-red absorbing form of phytochrome (Pfr). [ABSTRACT FROM AUTHOR]

With appropriate pretreatment of the seeds fluence-response curves for the induction of germination of Arabidopsis thaliana show two phases. A proportion of the population responds to very low fluence (VLFR). 10-4-10-2 μmol m-2, establishing 10-4 - 10-2% of the total phytochrome in the far-red absorbing form (Pfr) and a proportion of the population respond to low fluence (LFR), 1-1000 μmolm-2 establishing 1-75% Pfr. The VLFR is not normally seen because the pre-existing Pfr level satisfies the Pfr requirement or use of green safelight establishes more Pfr than necessary to saturate tire VLFR. Endogenous Pfr was depleted by a 24 h 35°C treatment, presumably as a result of dark destruction and/or dark reversion to the red absorbing form of phytochrome (Pr), making it possible to visualize the VLFR. A short pulse of 35°C treatment in combination with an appropriate temperature regime is also able to sensitize a proportion of the seed population. The proportion of the population showing tire VLFR is determined by the duration of the cold imbibition pretreatment as well as the duration of the 35°C treatment. Complex fluence-response curves were observed in which a proportion of the seeds being promoted in the VLFR range, were inhibited at higher fluences before being further promoted in the LFR range. This was particularly clear for seed batches being sensitized by a short 35°C treatment. The VLFR may be of significance in the natural environment, enabling seeds buried in the upper layer of the soil to germinate, where the fluence rate falls off sharply and the LFR is not satisfied. A model is presented to explain the two phases in the fluence-response curves. [ABSTRACT FROM AUTHOR]

The influence of different drying conditions on the chemical composition, physical properties, in vitro organic matter degradability and fermentation kinetics of forages was investigated using young and old grass (Lolium perenne) samples (harvested on 15 June and 9 July 1992 at Lelystad, The Netherlands) and young and old maize (Zea mays cv. Scana) stem samples (harvested on 19 August and 30 September 1991 at Lelystad). The samples were either freeze-dried with a maximum sample temperature of 10 °C, dried in a vacuum at 20 °C or air-dried at 30, 50, 70 and 105 °C. The different drying methods had little effect on ash, acid detergent fibre (ADF), acid detergent lignin (ADL), crude fibre and crude protein (CP) contents and in vitro degradation of the forage samples. However, some effects were found for sugars and phenolic acids. The neutral detergent fibre (NDF) content in protein-rich samples and the fermentation kinetics in rumen fluid differed significantly according to drying method. In samples dried other than by freeze-drying, proteins were bound to the NDF content and in some cases an effect on the amount of soluble sugars was also seen. Physical properties of the samples were determined by differential scanning calorimetry (DSC) and differences were found between freeze-dried materials and those dried at 70 °C. The influence of age on the maize samples was very pronounced, whereas it had little effect on the characteristics of the grass samples, with the exception of a decreased CP content and an increased sugar content after acid hydrolysis. [ABSTRACT FROM PUBLISHER]

Psychological, psychosocial, and psychophysiological sequelae were studied in a community which had experienced a railroad chemical spill of 19,000 gallons of the toxic pesticide metam sodium. Two hundred twenty exposed residents were compared to 114 controls and paired on age, education, gender, race, and number of children. A clinical interview and physiological measurements (blood pressure, pulse, and cortisol level) were taken, the MMPI-2, IES Scale, Mood Scale, Environmental Worry, Perceived Social Support, and Perceived Control Scale and a questionnaire were administered. Results indicated greater levels of depression, anxiety, and somatic symptoms in the spill residents in addition to greater environmental worry and lower perceived social support. Spill residents had higher blood pressure and less fluctuation of cortisol levels than controls. No difference on litigation status was obtained except on the IES, Intrusion and the POMS scales. Chemical disasters are associated with a wide variety of psychological, psychosocial, and physiological distress. [ABSTRACT FROM AUTHOR]

As the epidemic of the acquired immunodeficiency syndrome (AIDS) expands, the prevalence of the human immunodeficiency virus (HIV) infection in health care environments will increase and health care workers in many locations are likely to be at increased risk for exposure. The Fifth Annual Advances in Occupational Cancer Conference, held in December 1988 in San Francisco, addressed occupational HIV infection. Symposium participants concluded that the risk of HIV infection for health care workers is low but not zero. Implementation of universal blood and body fluid precautions was agreed to as an appropriate method of preventing exposure to HIV, especially for preventing needlestick accidents. Current standards for hospital waste disposal were judged to be adequate to prevent transmission of HIV, and confidential testing for HIV antibody in health care workers with follow-up counseling was recommended where indicated. It was also agreed that the risk of occupational exposure to HIV does not free health care workers from the responsibility to provide care to infected persons. [ABSTRACT FROM AUTHOR]