bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of small‐bore wire‐guided chest drains for management of pleural space disease
Authors: Valtolina C. , Adamantos S.
Published: June 2009

Objectives: To evaluate the efficacy and practicality of a small‐bore wire‐guided chest drain for management of pleural space disease in dogs and cats.

Materialsand Methods: A 14 gauge chest drain was placed using a modified Seldinger technique in animals requiring ongoing management of pleural space disease. A questionnaire was used immediately after placement to collect data regarding the ease of placement, reliability and function of the drain.

Results: Twenty animals were enrolled in which 29 drains were placed. The most common pleural space disease encountered was pyothorax (10 of 20). Sixteen animals required sedation for placement, and 25 of 29 chest drains were inserted at the first attempt. Most drains were placed in less than 10 minutes. The median length of time of catheter use was three days. Few complications were noted during the insertion and throughout the use of the drains. Clinicians rated drain placement as “easy” in 27 of 29 times and the drain function as “good” in 24 of 29 times.

Clinical Significance: Small‐bore wire‐guided chest drains are an effective alternative to larger gauge drains. Only minor complications were seen during insertion of the chest drains, and their performance was deemed satisfactory in most cases.
Assessment of companion animal quality of life in veterinary practice and research
Authors: Yeates J. , Main D.
Published: June 2009

Objectives: Quality‐of‐life (QOL) assessment is a novel field in veterinary medicine. It shares similarities with the more established fields of human QOL assessment and animal welfare science and could prove similarly useful.

Methods: This paper draws on existing literature on human QOL assessment, animal welfare, philosophy and animal QOL assessment.

Results: It provides practical recommendations for QOL assessment in veterinary practice and in veterinary research on what should be assessed, how it should be assessed and who should assess it.

Clinical Significance: These should assist veterinarians intending to develop their use QOL assessment.
Validation of a client‐based clinical metrology instrument for the evaluation of canine elbow osteoarthritis
Authors: Hercock C. A. , Pinchbeck G. , Giejda A. , Clegg P. D. , Innes J. F.
Published: June 2009

Objective:To validate a disease‐specific client‐based clinical metrology instrument (questionnaire) for dogs with chronic osteoarthritis of the elbow joint.

MaterialsandMethods:This was a prospective cohort study involving 26 dogs with chronic osteoarthritis of the elbow with 24 associated clients. Validity (face and criterion), reliability and responsiveness of the metrology instrument (named “Liverpool Osteoarthritis in Dogs [elbow]”) were tested in a sequence of studies. Face validity involved use of international peer review. Reliability was assessed using a test‐retest scenario with a two week interval; peak vertical force as measured by a force platform was used as an external standard measure. Responsiveness was tested with a two week, single‐blinded placebo‐controlled intervention using a licensed non‐steroidal anti‐inflammatory drug.

Results:The reliability of Liverpool Osteoarthritis in Dogs (elbow) in the test‐retest scenario was good; intraclass correlation coefficient is 0·89, 95 per cent confidence interval 0·75 to 0·95, compared with intraclass correlation coefficient 0·92, 95 per cent confidence interval 0·74 to 0·98, for peak vertical force. Responsiveness testing indicated that the “net” effect size (allowing for placebo effect) for Liverpool Osteoarthritis in Dogs (elbow) was 0·13 compared with (−)0·18 for the force platform. Criterion validity for Liverpool Osteoarthritis in Dogs (elbow) against peak vertical force was poor; Spearman’s rank correlation is −0·24 (P=0·30).

ClinicalSignificance:Liverpool Osteoarthritis in Dogs (elbow) was considered reliable with satisfactory responsiveness. The poor criterion validity suggests a mismatch between force platform peak vertical force and client perceptions of lameness. This instrument requires further validation in larger studies with alternative client groups and alternative therapeutic interventions, but this initial validation suggests that Liverpool Osteoarthritis in Dogs (elbow) is worthy of continued investigation.
Managing ‘difference’: understanding age diversity in practice
Authors: Riach Kathleen
Published: June 2009

This paper seeks to explore how age diversity is characterised, understood and managed by HR managers responsible for its implementation. With businesses competing at a global level and demographic trends changing the landscape of the labour market, the diversity approach to managing workplace equality has been heralded as the answer to the political and moral challenges in marrying external competition with internal workplace equality. Nowhere has this been more influential than in recent debates concerning older workers in the labour market, and yet, how age‐related HR practices relate to the underpinning philosophies of diversity has not yet been explored in any depth. Drawing from interview data with HR managers from a range of industry backgrounds, this article explores the inherent tensions faced when discussing age as a diversity issue, and the persistent effects of larger social norms related to ageing. By focusing on the concept of ‘difference’ as a key tenet of diversity, the challenges in ensuring equality while being aware of contradictory messages from both inside and outwith the organisations play a key role in age diversity in practice. This leads to a discussion about the more subtle practices involved in the workplace implementation of age diversity and how awareness of inherent biases may challenge age inequality within organisations.
Mentors, supervisors and role models: do they reduce the effects of psychological contract breach?
Authors: Zagenczyk Thomas J. , Gibney Ray , Kiewitz Christian , Restubog Simon Lloyd D.
Published: June 2009

Psychological contract breach has become a significant problem for many organisations in today's business environment because it fosters a belief within employees that the organisation does not support them. Accordingly, we examine whether organisations can diminish the negative impact of psychological contract breach on perceived organisational support (POS) by providing employees with mentors, supportive supervisors and role models. In Study 1, we found that mentor relationships moderated the relationship between psychological contract breach and POS six months later. In Study 2, we showed that mentor relationships and supervisor support reduced the negative impact of contract breach on POS. Contrary to expectations, employees who maintained relationships with role models reported lower levels of POS in response to psychological contract breach than those employees who reported that they did not have role models in their organisations. Implications for research and practice are discussed.
Equality and diversity in the public services: moving forward on lesbian, gay and bisexual equality?
Authors: Colgan Fiona , Wright Tessa , Creegan Chris , McKearney Aidan
Published: June 2009

A key change for lesbian, gay and bisexual (LGB) people in the European Union has been the prohibition by the Employment Equality Directive (2000) of discrimination in employment on grounds of sexual orientation. This article focuses on the UK, which in 2003 introduced legislation making it unlawful to discriminate on these grounds. It explores the factors encouraging ‘good practice’ in sexual orientation equality work. It considers progress within the public services that have ‘pioneered’ sexual orientation equalities work, drawing on the views of LGB employees, management and trade union stakeholders. The recent legislation is considered to have provided a major impetus for change; however, an emerging ‘business case’ within the public service modernisation agenda is considered to have provided both opportunities and barriers to progress. A challenge for HR practitioners is getting organisational commitment to sexual orientation work, which is still perceived within organisations as a ‘sensitive’ area.
Using competency‐based assessment centres to select judges – implications for equality and diversity
Authors: Kirton Gill , Healy Geraldine
Published: June 2009

This article is concerned with two significant areas of HR practice – competency‐based recruitment and selection and equality and diversity. The article provides a critical appraisal of the implications for equality and diversity of using a competency approach to select judges in the UK. The study reveals the socially constructed and ambiguous nature of competencies in practice. It offers partial support to previous claims that competency‐based HR practices have the potential to be used more creatively and inclusively and thus have the potential to further equality and diversity objectives. However, the study also revealed dangers inherent in competency‐based HR practices that arise from the inescapable fact that human, organisational actors (i.e. the assessors) are necessarily required to interpret the competencies and evaluate which candidates meet them and which do not. Thus, whatever the rhetoric, there is the potential for bias, prejudice and discrimination.
Employer responses to union organising: patterns and effects
Authors: Heery Edmund , Simms Melanie
Published: June 2009

This article presents original research on employer responses to trade union organising campaigns in the United Kingdom. The evidence indicates that there is no single response, with employers in some cases seeking to block and in others support union activity. These different patterns are strongly path dependent and reflect the prior degree of exposure to trade unionism of workplaces targeted for organising. Another finding is that employer responses co‐vary with union approaches to organising, such that when the employer adopts adversarial tactics so does the union. The militancy of both parties, it seems, is mutually reinforcing. Finally, the evidence points to substantial influence of employer responses over the outcomes of organising. When employers are supportive then campaigns tend to be more successful, measured on a range of criteria. When the employer is hostile unions find it difficult to make progress and encounter particular difficulties in securing recognition.
Evaluation of In Vitro Apparent Protein Digestibility by Shrimp Using Gut Enzyme Extracts
Authors: Fox Joe M , Lawrence Addison L
Published: June 2009

Knowledge of apparent protein digestibility (APD) is required for optimization of feed formulae for the production of marine penaeid shrimp. The purpose of this study was to evaluate an in vitro method for determining APD in marine penaeid shrimp using gut enzyme extracts. A high correlation (r2 = 0.95) was shown between single‐ingredient APD values for fish meal diets using in vivo methodology and those derived from in vitro testing of ingredients. A second study showed positive correlation (r2 = 0.71) between in vitro APD of selected purified and semipurified ingredients and their reported in vivo APDs. This correlation was much higher for purified ingredients (r2 = 0.93) versus less‐refined ingredients (r2 = 0.24). A third trial compared in vitro APD at three different enzyme extract pH values and showed that for most protein sources, APD was significantly highest (P < 0.05) at pH = 7.0 and lower at pH = 6.1 or 7.9, indicating a neutral pH optimum for this methodology.
Effect of Light Intensity on Color Performance of False Clownfish, Amphiprion ocellaris Cuvier
Authors: Yasir Inayah , Qin Jian G.
Published: June 2009

Color performance of false clownfish, Amphiprion ocellaris Cuvier, was examined under three levels of light intensity (20–50 , 600–850 , and 2700–3500 lx) for 5 wk. The experiment was conducted in nine rectangular glass aquaria (25 × 25 × 20 cm) with three replicates. Each aquarium was stocked with 36 fish, and 3 fish were randomly sampled from each aquarium every other week. Digital images were taken weekly on each individual fish after it was anesthetized in MS‐222. The color performance in hue, saturation, and brightness was quantified using image analysis. In addition to the whole‐body analysis, each fish image was divided into ventral and dorsal parts to assess the body position‐dependent effect. Furthermore, color differences between dorsal fin, anal fin, ventral fin, and caudal fin were also quantified. The whole body was brighter at low light than at medium or at high light intensity. Irrespective of light intensity, the dorsal side was more orange but less bright than the ventral side. Brighter light strengthened overall orange color on fish fins. The dorsal fin and ventral fins appeared more orange than the anal and caudal fins regardless of light intensity and exposure duration. Similar to body color, low light also led to brighter fins, especially for caudal and dorsal fins. Our results indicate that ambient light could regulate fish color performance but could not change the pigment dominance by β‐carotene. Light intensity is unlikely to change the contrast between dorsal and ventral sides, but dim light tends to make fish body brighter, and bright light strengthens orange color on fins.
Substitution of Balanced Feed with Chaya, Cnidoscolus chayamansa, Leaf in Tilapia Culture: A Bioeconomic Evaluation
Authors: Poot‐López Gaspar Román , Gasca‐Leyva Eucario
Published: June 2009

The main challenge for tilapia culture in rural areas of Mexico is low producer income and difficulty in acquiring inputs (fingerlings and balanced feed). In response, some rural producers feed tilapia with locally available vegetal inputs such as chaya, Cnidoscolus chayamansa. This plant is a bush endemic to the Yucatan Peninsula, Mexico, that is traditionally used for human and animal nutrition. In these rural culture systems, chaya is provided ad libitum as fresh leaves. Its use to date is empirical, and therefore, little is known about optimum substitution levels. A bioeconomic model was developed using experimental data. The von Bertalanffy model was parameterized using chaya/balanced feed combinations that produced growth not statistically different than a diet with sole use of balanced feed. This model included biological, economic, and management components. The results indicate that balanced feed can be substituted by chaya leaves at up to 50% and that this substitution level provides the lowest production costs during the warm season. Maintenance of this production level requires 2.23 units of chaya per unit of balanced feed, with the restriction that only 50% of the ration can be substituted by chaya leaves.
Spawning of the Temperate Sea Cucumber, Australostichopus mollis (Levin)
Authors: Morgan Andrew David
Published: June 2009

The spawning of sea cucumbers is related to the interaction of environmental cues and reproductive maturity. Groups of Australostichopus mollis were collected every 2 wk during the summer reproductive season from mid‐October to early February. They were observed for spawning in the hatchery during heat‐shock trials conducted 3–5 C above ambient seawater temperature. Lunar periodicity existed with spawning being most prominent in the week following a full moon. In the week prior to a spawning event, there was also a decrease in ambient incoming seawater temperature. More than 75% individuals spawned during most trials in which spawning occurred. In total, 40% of the 270 individuals spawned during the reproductive season. Reliable spawners were females with a yellow gonad color and large numbers of vitellogenic oocytes, and males with large numbers of spermatocytes and an absence of motile spermatozoa. Furthermore, the percentage germinal vesicle breakdown of oocytes exposed to starfish radial nerve extract compared to seawater was greater for the more orange‐colored gonad of nonspawners. Gonad color is useful in determining the likelihood of spawning over a 2‐wk period in the presence of a cue. Sea cucumbers held for short periods in the hatchery during the reproductive season maintain a natural rhythm of spawning that can be monitored using visual indices and augmented using heat shock.
Effects of Salinity on Growth and Energy Budget of Juvenile Cobia,Rachycentron canadum
Authors: Chen Gang , Wang Zhongliang , Wu Zaohe , Gu Binhe , Wang Zhongliang , Wang Zhongliang , Wu Zaohe
Published: June 2009

The effects of salinity on the growth and energy budget of juvenile cobia,Rachycentron canadum, were evaluated. Triplicate tanks with ten fish per tank (initial weight 17.58 ± 0.26 g/fish, mean ± SD) reared at salinities of 5, 10, 15, 20, 25, 30, and 35 ppt were fed with fresh squid to satiety for 15 d. Results indicated that there were no significant differences in daily ration level in wet weight (RLw), dry weight (RLd), and energy (RLe) of the fish. There were also no significant variations in daily fecal production (fe) and apparent digestibility coefficient of energy (ADCe) among salinity treatments. Specific growth rates (SGRs) in wet weight (SGRw), dry weight (SGRd), and energy (SGRe) showed domed curves relative to salinity. Quadratic regression analyses of SGRw, SGRd, and SGReagainst salinity indicated that the optimal salinity for maximal growth of juvenile cobia was 29.9, 29.9, and 28.5 ppt, respectively. Similar to the trend of SGR, food conversion efficiency for juvenile cobia in wet weight (FCEw), dry weight (FCEd), and energy (FCEe) increased with the increases in salinity, maximized at 30 ppt, and then decreased when salinity reached 35 ppt.
Effect of Initial Stocking Density on Larviculture Performance of the Ocellate Puffer, Takifugu rubripes
Authors: Kotani Tomonari , Wakiyama Yoshiyuki , Imoto Tatsuhiro , Suzuki Hisahide , Fushimi Hiroshi
Published: June 2009

Depending on the initial stocking density, ocellate puffer larvae exhibit the cannibalism that resulted in high mortality. We aimed to clarify the relationship between stocking density of larvae, mortality, and the effect of density on cannibalism. Ocellate puffer larvae were reared at five different stocking densities between 5 and 25 larvae/L with duplicate 1‐m3 tank for each treatment. Larvae were stocked at 0 d after hatch (d.a.h.), and the experimental cultures lasted for 55 d. In larvae stocked initially at more than 10 larvae/L, cannibalism was evident from 11 to 17 d.a.h., and the survival rate at 55 d.a.h. was less than 15%. The survival rate was 25.5% at 5 larvae/L, and cannibalism was observed from 31 to 32 d.a.h. Consequently, an initial density of 5 larvae/L was the most efficient in terms of survival and the prevention of cannibalism. On the other hand, when cannibalism is still observed at 5 larvae/L, it is necessary to lower the stocking density before the onset of cannibalism.
Prey Selectivity and Trophic Behavior of the Patagonian Seahorse, Hippocampus patagonicus, in Captivity
Authors: Storero Lorena P. , González Raúl A.
Published: June 2009

This study aims at evaluating the Patagonian seahorse, Hippocampus patagonicus, feeding behavior in captivity with regard to type and size of prey selectivity and time‐investment‐related activities for searching and capture. Experiments in aquaria were carried out under two different treatments, with and without refuge for prey. Different diets composed of amphipods (Melita palmata and Ampithoe valida), juvenile decapods (Neohelice granulata) from natural environments, and artificially cultured Artemia salina. The eaten prey’s size was analyzed and experiments with size‐controlled prey were carried out. There were neither significant differences in the prey quantity ingested between males and females nor between treatments (with or without refuge). However, significant differences were found between the quantities of each prey consumed. Amphipods and A. salina were consumed in greater quantity (P < 0.05) when compared with juvenile decapods. Experiments with A. salina of different sizes did not show significant differences on seahorses’ preference. N. granulata was highly avoided and seahorses had lower capture efficiency over this prey. Behavioral observations showed that more than 50% of the times seahorses were resting and ambushing their prey. In captivity, with optimal conditions for predation, the Patagonian seahorse modifies its opportunistic behavior, feeding selectively, and bases its food preferences on prey size and shape.
Evaluation of a Barrier Confinement System for Channel Catfish, Ictalurus punctatus, Production
Authors: Pugliese Neil J , Heikes David , Engle Carole R
Published: June 2009

An in‐pond confinement system to separate channel catfish, Ictalurus punctatus, by size within a single pond provides an opportunity for improved growth of understocked fish in ponds with larger market‐sized fish. A barrier of polyvinyl chloride–coated galvanized wire mesh was constructed in five 0.10‐ha earthen ponds to partition the pond into one‐third and two‐third sections, while five other 0.10‐ha ponds were left as traditional open ponds for a control. To evaluate catfish performance in this confinement system, fingerlings (25 g) were stocked at 14,820/ha into the smaller one‐third section of the barrier and carryover fish (408 g) at 2580 kg/ha into the larger two‐third section of the barrier. The control ponds were stocked with the same sizes and numbers of fish in a traditional earthen pond without a barrier. Yield, survival, feed conversion ratio (FCR), growth, and economics were compared between treatments. Fingerling yields were greater in the barrier system that allowed fingerlings to be separated physically from larger carryover fish. There were no differences in yield of carryover fish, survival, FCR, or growth between the control and the barrier ponds. Partial budget analysis revealed a positive net change of $367/ha or $38,125 for a 104‐ha catfish farm (at a market price of $1.54/kg of additional stockers produced). The value of the greater weight of understocked fish produced in the barrier system was greater than the annualized cost of installing the barrier, for farmers raising fish in multiple batch. Thus, on an experimental basis, the confinement system was economically profitable; however, trials on commercial farms are needed to evaluate performance on a larger scale.
Methionine Requirement in Practical Diets of Juvenile Nile Tilapia, Oreochromis niloticus
Authors: Nguyen Tri N , Allen Davis D
Published: June 2009

Two feeding experiments were conducted to confirm methionine requirement in practical diets of juvenile Nile tilapia, Oreochromis niloticus. Test diets used in both experiments contained 414 kcal gross energy, 28 g protein, and 5 g lipid per 100 g diet. In the first experiment, seven diets were made using cottonseed meal (CSM), dehulled solvent‐extracted soybean meal (DSESM), and gelatin as intact protein sources. Methionine was added to five of these diets at 0.03 or 0.06% increments to produce methionine levels ranging from 0.33 to 0.57% of the diet. Each diet was fed to four replicate groups of male juvenile Nile tilapia (5.62 ± 0.13 g) in a recirculation system for 8 wk. Broken‐line regression analysis of weight gain indicated that methionine requirement of juvenile Nile tilapia was 0.49% of the diet or 1.75% of dietary protein at cystine level of 0.45% of the diet. The second experiment was designed based on methionine requirement determined in the first experiment and also contained seven test diets. The first six diets contained CSM and DSESM as protein sources. Methionine was added to five of these diets at an increasing rate of 0.06% to produce methionine levels ranging from 0.49 to 0.79% of the diet. In the last diet (Diet 7), a portion of DSESM was replaced by gelatin to reduce methionine level to 0.33% of the diet in order to test whether methionine is limited. Each diet was also fed to four replicate groups of male juvenile Nile tilapia (2.32 ± 0.06 g) in a recirculation system for 9 wk. At the termination of the second experiment, there were no significant differences in terms of weight gain, survival, and feed efficiency ratio (FER) among the fish fed the first six diets. However, weight gain and FER of the fish fed these diets were significantly better than those fed Diet 7, confirming the methionine requirement value as has been determined in the first experiment.
Contribution of Fish Production to Farmers’ Subjective Well‐being in Vietnam – A Logistic Model
Authors: Duc Nguyen Minh
Published: June 2009

There is a growing awareness of the importance of food fish production on human nutrition, employment, poverty, and recreation. However, the role of aquaculture in livelihoods of fish farmers has not been considered rigorously. With 120 farmers interviewed in a field survey and a cumulative logistic model, this study identifies some determinants of subjective well‐being of small‐scale fish farmers in Vietnam and examines the role of earnings from fish production in generating their happiness. The results confirm that the farmers receive satisfaction from their farm working. Subjective well‐being of the farmers increases with their job satisfaction and cash earnings from fish farming. A doubling in cash returns from fish culture relative to household income raises a farmer’s happiness probability by an estimated 10.6%. Education also affects farmers’ life satisfaction. For better educated farmers, when their satisfaction from fish culture increases by one level, happiness probability is estimated to increase by 0.23%. Wild fish plays an important role in Vietnamese farmers as a doubling in relative income from wild fish captures raises their estimated probability of happiness by 139%.
Rapid Profiling of Swiss Cheese by Attenuated Total Reflectance (ATR) Infrared Spectroscopy and Descriptive Sensory Analysis
Authors: Kocaoglu‐Vurma N.A. , Eliardi A. , Drake M.A. , Rodriguez‐Saona L.E. , Harper W.J.
Published: June 2009

ABSTRACT: The acceptability of cheese depends largely on the flavor formed during ripening. The flavor profiles of cheeses are complex and region‐ or manufacturer‐specific which have made it challenging to understand the chemistry of flavor development and its correlation with sensory properties. Infrared spectroscopy is an attractive technology for the rapid, sensitive, and high‐throughput analysis of foods, providing information related to its composition and conformation of food components from the spectra. Our objectives were to establish infrared spectral profiles to discriminate Swiss cheeses produced by different manufacturers in the United States and to develop predictive models for determination of sensory attributes based on infrared spectra. Fifteen samples from 3 Swiss cheese manufacturers were received and analyzed using attenuated total reflectance infrared spectroscopy (ATR‐IR). The spectra were analyzed using soft independent modeling of class analogy (SIMCA) to build a classification model. The cheeses were profiled by a trained sensory panel using descriptive sensory analysis. The relationship between the descriptive sensory scores and ATR‐IR spectra was assessed using partial least square regression (PLSR) analysis. SIMCA discriminated the Swiss cheeses based on manufacturer and production region. PLSR analysis generated prediction models with correlation coefficients of validation (rVal) between 0.69 and 0.96 with standard error of cross‐validation (SECV) ranging from 0.04 to 0.29. Implementation of rapid infrared analysis by the Swiss cheese industry would help to streamline quality assurance.
Sulfur‐Containing Compounds Heated under Alkaline Condition: Antibrowning, Antioxidative Activities, and Their Effect on Quality of Shrimp during Iced Storage
Authors: Phonpala Yoottana , Benjakul Soottawat , Visessanguan Wonnop , Eun Jong‐Bang
Published: June 2009

ABSTRACT:  Sulfur‐containing compounds heated under alkaline condition (pH 10) were determined for inhibitory activity toward polyphenol oxidase (PPO) from Pacific white shrimp (Litopenaeus vannamei) and for antioxidative activity. Cysteine and glutathione (GSH) (20 mM) heated at 100 °C at pH 10 strongly inhibited PPO activity. Heated alkaline cysteine showed the greater 2,2‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) and 2,2‐diphenyl‐1‐picryl hydrazyl (DPPH) radical scavenging activity, copper‐chelating activity and reducing power than cysteine and glucose–cysteine Maillard reaction products (P < 0.05). Effect of heated alkaline cysteine at different concentrations (0, 20, and 100 mM) on the quality changes of Pacific white shrimp during iced storage was investigated. Shrimp treated with 100 mM heated alkaline cysteine had the lowest melanosis score, thiobarbituric acid‐reactive substances (TBARS) value and total viable count (TVC), compared with those without treatment and treated with 20 mM heated alkaline cysteine, throughout the storage of 12 d (P < 0.05). Therefore, heated alkaline cysteine can be used as a novel additive to retard melanosis and extend the quality of postmortem shrimp.
The Green Oat Story: Possible Mechanisms of Green Color Formation in Oat Products during Cooking
Authors: Doehlert D.C. , Simsek S. , Wise M.L.
Published: June 2009

ABSTRACT:  Consumers occasionally report greenish colors generated in their oat products when cooking in tap water. Here we have investigated pH and ferrous (Fe2+) ion as possible mechanisms for this color change. Steel‐cut oat groats can turn brown‐green color when cooked in alkaline conditions (pHs 9 to 12). Extraction of this color with methanol, and high‐pressure liquid chromatography indicated a direct association of this color with the phenolic acid or avenanthramide content of the oat. The presence of 50 mM NaHCO3 in water will cause oat/water mixtures to turn alkaline when cooked as CO2 is driven off, generating OH− ion. Although tap water rarely, if ever, contains so much bicarbonate, bicarbonate is used as a leavening agent in baking applications. Industrial interests using baking soda or alkaline conditions during oat processing should be aware of possible off color generation. We have also found that as little as 10 ppm Fe2+ will turn oat products gray‐green when cooked. The aleurone stained darker than the starchy endosperm. Other divalent cations, such as Ca2+ or Mg2+ had no effect on cooked oat color. As much as 50 ppm Fe2+ may be found in freshly pumped well water, but Fe2+ reacts quickly with oxygen and precipitates as Fe(OH)3. Thus, some freshly pumped well water may turn oats green when cooked, but if the water is left under atmospheric conditions for several hours, no discoloration will appear in the cooked oats.
Color Formation in Nitrite‐Free Dried Hams as Related to Zn‐Protoporphyrin IX and Zn‐Chelatase Activity
Authors: Parolari Giovanni , Benedini Riccardo , Toscani Tania
Published: June 2009

ABSTRACT:  The development of red pigment Zn‐protoporphyrin IX (ZPP) in nitrite‐free Parma hams was investigated in 5 leg muscles at several stages of processing and the activity of muscle Zn‐chelatase was concurrently assayed for its potential role in ZPP formation. A steady increase of the pigment was observed throughout the manufacturing stages at mild temperatures while no development was observed during the prior cold resting phase. The enzyme was partly inactivated according to a muscle‐dependent pattern, resulting in similar ZPP contents, hence color, in finished hams. It is concluded that enzyme‐dependent synthesis of ZPP in nitrite‐free dried hams contributes to color development, enabling muscles in dried hams to become more similar in redness than in green thighs. Therefore, checking raw meat for the enzyme content may be a means to control color formation in nitrite‐free dry‐cured meat derivatives.
Regulation and compartmentalization of β‐lactam biosynthesis
Authors: Martín Juan F. , Ullán Ricardo V. , García‐Estrada Carlos
Published: June 2009

Penicillins and cephalosporins are β‐lactam antibiotics widely used in human medicine. The biosynthesis of these compounds starts by the condensation of the amino acids l‐α‐aminoadipic acid, l‐cysteine and l‐valine to form the tripeptide δ‐l‐α‐aminoadipyl‐l‐cysteinyl‐d‐valine catalysed by the non‐ribosomal peptide ‘ACV synthetase’. Subsequently, this tripeptide is cyclized to isopenicillin N that in Penicillium is converted to hydrophobic penicillins, e.g. benzylpenicillin. In Acremonium and in streptomycetes, isopenicillin N is later isomerized to penicillin N and finally converted to cephalosporin. Expression of genes of the penicillin (pcbAB, pcbC, pendDE) and cephalosporin clusters (pcbAB, pcbC, cefD1, cefD2, cefEF, cefG) is controlled by pleitropic regulators including LaeA, a methylase involved in heterochromatin rearrangement. The enzymes catalysing the last two steps of penicillin biosynthesis (phenylacetyl‐CoA ligase and isopenicillin N acyltransferase) are located in microbodies, as shown by immunoelectron microscopy and microbodies proteome analyses. Similarly, the Acremonium two‐component CefD1–CefD2 epimerization system is also located in microbodies. This compartmentalization implies intracellular transport of isopenicillin N (in the penicillin pathway) or isopenicillin N and penicillin N in the cephalosporin route. Two transporters of the MFS family cefT and cefM are involved in transport of intermediates and/or secretion of cephalosporins. However, there is no known transporter of benzylpenicillin despite its large production in industrial strains.
Quantitative Separation of Molybdenum and Rhenium from Geological Materials for Isotopic Determination by MC‐ICP‐MS
Authors: Pearce Christopher R. , Cohen Anthony S. , Parkinson Ian J.
Published: June 2009

We have developed a new chemical procedure for the quantitative separation of molybdenum (Mo) and rhenium (Re) from a wide variety of geological samples. A single pass anion exchange separation provided complete recovery of pure Mo and Re in a form that was ideal for subsequent isotope and abundance determination by multi‐collector inductively coupled plasma‐mass spectroscopy (MC‐ICP‐MS). An enriched 100Mo‐97Mo solution, mixed with the sample before digestion, enabled natural mass‐dependant isotopic fractionation of Mo to be determined with an external reproducibility of < 0.12‰ (δ98Mo/95Mo, 2s). Determination of the concentration of Mo and Re in the same sample was achieved by isotope dilution, with instrumental mass‐fractionation of Re being corrected by the simultaneous measurement of the 191Ir/193Ir ratio. We have applied the new procedure to a variety of samples, including seawater, basalt and organic‐rich mudrock. The procedure is ideally suited to palaeoredox studies requiring the precise determination of the Mo isotope composition and the Re/Mo ratio from the same sample.
Laser Ablation (193 nm), Purification and Determination of Very Low Concentrations of Solar Wind Nitrogen Implanted in Targets from the GENESIS Spacecraft
Authors: Zimmermann Laurent , Burnard Pete , Marty Bernard , Gaboriaud Fabien
Published: June 2009

The GENESIS space mission recovered ions emitted by the Sun during a 27 month period. In order to extract, purify and determine the very low quantities of solar nitrogen implanted in the GENESIS targets, a new installation was developed and constructed at the CRPG (Nancy, France). It permitted the simultaneous determination of nitrogen and noble gases extracted from the target by laser ablation. The extraction procedure used a 193 nm excimer laser that allowed for surface contamination in the outer 5 nm to be removed, followed by a step that removed 50 nm of the target material, extracting the solar nitrogen and noble gases implanted in the target. Following purification using Ti and Zr getters for noble gases and a Cu‐CuO oxidation cycle for N2, the extracted gases were analysed by static mode (pumps closed) mass spectrometry using electron multiplier and Faraday cup detectors. The nitrogen blanks from the purification section and the static line (30 minutes) were only 0.46 picomole and 0.47 picomole, respectively.
Measurement of SIMS Instrumental Mass Fractionation of Pb Isotopes During Zircon Dating
Authors: Stern Richard A. , Bodorkos Simon , Kamo Sandra L. , Hickman Arthur H. , Corfu Fernando
Published: June 2009

An igneous zircon reference material (OG1) was characterised for U‐Pb isotopes by ID‐TIMS, and utilised to evaluate SIMS (SHRIMP) instrumental mass fractionation (IMF) of radiogenic Pb isotopes (207Pb*/206Pb*). The TIMS 207Pb*/206Pb* reference value for OG1 was 0.29907 ± 0.00011 (95% confidence limit), 3465.4 ± 0.6 Ma. The high 207Pb* (∼ 30 μg g−1), negligible common Pb, and isotopic homogeneity permitted precise (± 1–2‰) 207Pb*/206Pb* measurements within the analytical sessions. External reproducibility of mean 207Pb*/206Pb* ratios between sessions was demonstrated for one instrument, yielding a mean IMF of +0.87 ± 0.49‰. The mean 207Pb*/206Pb* ratios between instruments were dispersed beyond uncertainties, with session IMF values from +3.6 ± 1.7‰ to −2.4 ± 1.3‰, and a grand mean IMF value (twenty‐six sessions) of +0.70 ± 0.52‰, indicating a tendency towards elevated 207Pb*/206Pb*. The specific causes of variability in IMF are unclear, but generally reflect subtle differences in analytical conditions. The common practice in SIMS of assuming that IMF for Pb+ is insignificant could result in systematic age biases and underestimated uncertainties, of critical importance for precise correlation of Precambrian events. Nevertheless, a zircon RM such as OG1 can be readily incorporated into routine dating to improve 207Pb*/206Pb* accuracy and external reproducibility.
Simultaneous Determination of Total Carbon, Nitrogen, Hydrogen and Sulfur in Twenty‐seven Geological Reference Materials by Elemental Analyser
Authors: Kubota Ran
Published: June 2009

The contents of total carbon, hydrogen, nitrogen and sulfur in twenty‐seven geological reference materials, issued by five producer organisations (USGS, CCRMP, ANRT, NIST and GSJ) were determined using an automated simultaneous elemental analyser following combustion. In order to complete gasification of C and N in some geological materials, the combustion temperature needed to be greater than 1150 °C. The calibrator prepared from known amounts of reagent material was not adopted for more than 1.2% m/m of H. Unrealistically high values in certain materials supposed to contain less than 1000 μg g−1 S may be due mainly to memory effects. The limit of detection was 50 μg g−1 for C and N, 500 μg g−1 for H and 1000 μg g−1 for S. Although the blank value of C and N was always stable and less than one third of the detection limit, it had a slightly higher value for N and S. By repeating long‐term analysis, high reproducibility for each of the four elements was verified. The method has been applied satisfactorily to a variety of geological reference materials, and recommended values for C, H and N for most of the reference materials studied have been tabulated.
GIS‐Based Spatial Precipitation Estimation: A Comparison of Geostatistical Approaches1
Authors: Zhang Xuesong , Srinivasan Raghavan
Published: June 2009

Abstract: As one of the primary inputs that drive watershed dynamics, the estimation of spatial variability of precipitation has been shown to be crucial for accurate distributed hydrologic modeling. In this study, a Geographic Information System program, which incorporates Nearest Neighborhood (NN), Inverse Distance Weighted (IDW), Simple Kriging (SK), Ordinary Kriging (OK), Simple Kriging with Local Means (SKlm), and Kriging with External Drift (KED), was developed to facilitate automatic spatial precipitation estimation. Elevation and spatial coordinate information were used as auxiliary variables in SKlm and KED methods. The above spatial interpolation methods were applied in the Luohe watershed with an area of 5,239 km2, which is located downstream of the Yellow River basin, for estimating 10 years’ (1991‐2000) daily spatial precipitation using 41 rain gauges. The results obtained in this study show that the spatial precipitation maps estimated by different interpolation methods have similar areal mean precipitation depth, but significantly different values of maximum precipitation, minimum precipitation, and coefficient of variation. The accuracy of the spatial precipitation estimated by different interpolation methods was evaluated using a correlation coefficient, Nash‐Sutcliffe efficiency, and relative mean absolute error. Compared with NN and IDW methods that are widely used in distributed hydrologic modeling systems, the geostatistical methods incorporated in this GIS program can provide more accurate spatial precipitation estimation. Overall, the SKlm_EL_X and KED_EL_X, which incorporate both elevation and spatial coordinate as auxiliary into SKlm and KED, respectively, obtained higher correlation coefficient and Nash‐Sutcliffe efficiency, and lower relative mean absolute error than other methods tested. The GIS program developed in this study can serve as an effective and efficient tool to implement advanced geostatistics methods that incorporate auxiliary information to improve spatial precipitation estimation for hydrologic models.
Predicting the Fate and Transport ofE. coliin Two Texas River Basins Using a Spatially Referenced Regression Model1
Authors: Puri Deepti , Karthikeyan R. , Babbar‐Sebens M.
Published: June 2009

Abstract: The two main rivers of southeast Texas: Guadalupe and San Antonio have shown high temporal increase in bacteria concentration during the last decade. The SPAtially Referenced Regression On Watershed (SPARROW) attributes model, developed by the U.S. Geological Survey (USGS), has been applied to predict the fluxes and concentrations of contaminants in unmonitored streams and to identify the sources of these contaminants. This model identifies every reach as a basic network unit to distribute the sources, delivery, and attenuation factors. The model is data intensive and implements nonlinear regression to solve the parsimonious relations for describing various watershed processes. This study explored watershed and hydrological characteristics (land uses, precipitation, human and animal population, point sources, areal hydraulic load and drainage density, etc.) as the probable sources and delivery mechanisms of waterborne pathogens and their indicator (Escherichia coli[E. coli]) in the Guadalupe and San Antonio River basins. The effect of using various statistical indices for model selection on the final model’s ability to explain the variousE. colisources and transport processes was also analyzed.
Spatial Variability of Nitrate Concentrations Under Diverse Conditions in Tributaries to a Lake Watershed1
Authors: Golden Heather E. , Boyer Elizabeth W. , Brown Michael G. , Purucker S. Thomas , Germain René H.
Published: June 2009

Abstract:  Nitrate‐nitrogen (NO3‐N) concentrations in stream water often respond uniquely to changes in inter‐annual conditions (e.g., biological N uptake and precipitation) in individual catchments. In this paper, we assess (1) how the spatial distribution of NO3‐N concentrations varies across a dense network of nonnested catchments and (2) how relationships between multiple landscape factors [within whole catchments and hydrologically sensitive areas (HSAs) of the catchments] and stream NO3‐N are expressed under a variety of annual conditions. Stream NO3‐N data were collected during two synoptic sampling events across >55 tributaries and two synoptic sampling periods with >11 tributaries during summer low flow periods. Sample tributaries drain mixed land cover watersheds ranging in size from 0.150 to 312 km2 and outlet directly to Cayuga Lake, New York. Changes in NO3‐N concentration ratios between each sampling event suggest a high degree of spatial heterogeneity in catchment response across the Cayuga Lake Watershed, ranging from 0.230 to 61.4. Variations in NO3‐N concentrations within each of the large synoptic sampling events were also high, ranging from 0.040 to 8.7 mg NO3‐N/l (March) and 0.090 to 15.5 mg NO3‐N/l (October). Although Pearson correlation coefficients suggest that this variability is related to multiple landscape factors during all four sampling events, partial correlations suggest percentage of row crops in the catchments as the only similar factor in March and October and catchment area as the only factor during summer low flows. Further, the strength of the relationships is typically lower in the HSAs of catchment. Advancing current understanding of such variations and relationships to landscape factors across multiple catchments – and under a variety of biogeochemical and hydrological conditions – is important, as (1) nitrate continues to be employed as an indicator of regional aquatic ecosystem health and services and (2) a unified framework approach for understanding individual catchment processes is a rapidly evolving focus for catchment‐based science and management.
The Watershed Deposition Tool: A Tool for Incorporating Atmospheric Deposition in Water‐Quality Analyses1
Authors: Schwede Donna B. , Dennis Robin L. , Bitz Mary Ann
Published: June 2009

Abstract:  A tool for providing the linkage between air and water‐quality modeling needed for determining the Total Maximum Daily Load (TMDL) and for analyzing related nonpoint‐source impacts on watersheds has been developed. Using gridded output of atmospheric deposition from the Community Multiscale Air Quality (CMAQ) model, the Watershed Deposition Tool (WDT) calculates average per unit area and total deposition to selected watersheds and subwatersheds. CMAQ estimates the wet and dry deposition for all of its gaseous and particulate chemical species, including ozone, sulfur species, nitrogen species, secondary organic aerosols, and hazardous air pollutants at grid scale sizes ranging from 4 to 36 km. An overview of the CMAQ model is provided. The somewhat specialized format of the CMAQ files is not easily imported into standard spatial analysis tools. The WDT provides a graphical user interface that allows users to visualize CMAQ gridded data and perform further analyses on selected watersheds or simply convert CMAQ gridded data to a shapefile for use in other programs. Shapefiles for the 8‐digit (cataloging unit) hydrologic unit code polygons for the United States are provided with the WDT; however, other user‐supplied closed polygons may be used. An example application of the WDT for assessing the contributions of different source categories to deposition estimates, the contributions of wet and dry deposition to total deposition, and the potential reductions in total nitrogen deposition to the Albemarle‐Pamlico basin stemming from future air emissions reductions is used to illustrate the WDT capabilities.
A Comparison of Statistical Approaches for Predicting Stream Temperatures Across Heterogeneous Landscapes1
Authors: Wehrly Kevin E. , Brenden Travis O. , Wang Lizhu
Published: June 2009

Abstract:  Estimating stream temperatures across broad spatial extents is important for regional conservation of running waters. Although statistical models can be useful in this endeavor, little information exists to aid in the selection of a particular statistical approach. Our objective was to compare the accuracy of ordinary least‐squares multiple linear regression, generalized additive modeling, ordinary kriging, and linear mixed modeling (LMM) using July mean stream temperatures in Michigan and Wisconsin. Although LMM using low‐rank thin‐plate smoothing splines to measure the spatial autocorrelation in stream temperatures was the most accurate modeling approach; overall, there were only slight differences in prediction accuracy among the evaluated approaches. This suggests that managers and researchers can select a stream temperature modeling approach that meets their level of expertise without sacrificing substantial amounts of prediction accuracy. The most accurate models for Michigan and Wisconsin had root mean square errors of 2.0‐2.3°C, suggesting that only relatively coarse predictions can be produced from landscape‐based statistical models at regional scales. Explaining substantially more variability in stream temperatures likely will require the collection of finer‐scale hydrologic and physiographic data, which may be cost prohibitive for monitoring and assessing stream temperatures at regional scales.