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1.
JDS Commun ; 3(1): 66-71, 2022 Jan.
Article in English | MEDLINE | ID: mdl-36340676

ABSTRACT

The objective of this study was to determine whether associations exist between position while ruminating (lying vs. standing) and milk and component production in dairy cows. Data from 30 lactating Holstein cows were assembled from 2 studies in which cows were milked by automated milking system (AMS) and fed a partial mixed ration (PMR) in feed bins that recorded intake behavior. Rumination and lying behavior were monitored using automated neck- and leg-based sensors, respectively. Each cow was monitored over 2 separate 2-wk treatment periods. To estimate position while ruminating for each 2-h period of the day for each cow, a conditional probability was calculated to determine the probability that any rumination time and lying time were occurring at the same time in any 2-h period. These probabilities (RwL), and all behavioral data, were summarized per cow per 2-h interval, and then averaged per day and per 2-wk period, along with milk yield and component data. Cows averaged (mean ± standard deviation) 1.9 ± 1.1 lactations and 85.5 ± 55.2 d in milk, and weighed 668.5 ± 96.0 kg. Data included rumination time (557.7 ± 41.1 min/d), lying time (703.9 ± 65.3 min/d), idle standing time (520.1 ± 83.2 min/d), PMR feeding time (204.7 ± 48.5 min/d), PMR dry matter intake (DMI; 21.8 ± 4.6 kg/d), AMS pellet provision (4.6 ± 1.6 kg/d), total DMI (26.4 ± 4.5 kg/d), milk yield (42.4 ± 7.2 kg/d), milk fat content (3.75 ± 0.51%), and milk protein content (3.21 ± 0.32%). Greater rumination time and lying time were associated with greater RwL probability (mean = 0.19 ± 0.02; range = 0.14 to 0.23). The RwL probability tended to be positively associated with total DMI and milk fat content, was associated with milk protein content, but was not associated with any measures of milk yield. The results indicate that in a free-traffic AMS, cows who have greater probability of ruminating while lying down spend more time ruminating and lying, and tend to consume more total dry matter and produce milk with greater components.

3.
Int J Cardiol Hypertens ; 2: 100012, 2019 Aug.
Article in English | MEDLINE | ID: mdl-33447745

ABSTRACT

Inconsistencies in studies of chronic psychosocial stress and hypertension may be explained by the use of stress markers greatly influenced by circadian rhythm and transient stressors. We assessed whether hair cortisol, a marker that captures systemic cortisol over months, was independently associated with hypertension. We measured hair cortisol and blood pressure in 75 consecutive participants in the Survey of the Health of Wisconsin, using an ELISA test. Individuals with values â€‹≥ â€‹median (78.1 â€‹pg/mg) were considered exposed. We used approximate Bayesian logistic regression, with a prior odds ratio of 1.0-4.0, to quantify the multivariate-adjusted hair cortisol-hypertension association. Participants' average age was 46.9 years; 37.3% were male; and 25.3% were hypertensive. Hypertension prevalence was 2.23 times higher in exposed (95% CI: 1.69-3.03). This finding was unlikely explained by differential measurement errors, since we conducted blinded measurements of exposure and outcome. Sensitivity analyses showed the association was unlikely explained by an unmeasured confounder, survival bias, or reverse causality bias. Findings suggest elevated hair cortisol is a risk factor for hypertension. Although feasible, the clinical value of hair cortisol as a tool for hypertension risk stratification or for monitoring the effect of chronic psychosocial stress management interventions is still uncertain.

4.
Rev Sci Instrum ; 83(6): 063107, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22755615

ABSTRACT

A laser stabilization scheme using magnetic dichroism in a RF plasma discharge is presented. This method has been used to provide a frequency stable external-cavity diode laser that is locked to the 4s[3/2](2) → 4p[5/2](3) argon laser cooling transition at 811.53 nm. Using saturated absorption spectroscopy, we lock the laser to a Doppler free peak which gave a locking range of 20 MHz when the slope of the error signal was maximized. The stability of the laser was characterized by determining the square root Allan variance of laser frequency fluctuations when the laser was locked. A stability of 129 kHz was measured at 1 s averaging time for data acquired over 6000 s.

5.
Faraday Discuss ; 142: 175-90; discussion 221-55, 2009.
Article in English | MEDLINE | ID: mdl-20151544

ABSTRACT

We propose a general scheme for sympathetic cooling of molecules to microK temperatures on a timescale of seconds. Experimental parameters have been estimated from theory, which indicate the viability of the scheme. This method, which is particularly suited to optical Stark deceleration, utilises ultracold, laser cooled metastable rare gas atoms quenched to their ground state as collision partners to co-trapped molecular species within a deep optical trap (150 mK). We also describe the measurement of the role of laser-induced molecular alignment on the dipole force in optical Stark deceleration and outline progress towards the realisation of chirped optical Stark deceleration for producing slow molecular beams with mK energy spreads.

6.
Transplant Proc ; 40(2): 430-2, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18374091

ABSTRACT

OBJECTIVE: Islet cell transplantation, as a treatment for type 1 diabetes mellitus, has historically required islet infusions from more than one donor organ to achieve insulin independence. Significant islet mass may be destroyed upon infusion due to a yet undefined process known as instant blood-mediated inflammatory reaction (IBMIR). Our objective was to identify gene expression changes in islets undergoing a simulated process of IBMIR. MATERIALS AND METHODS: Human pancreatic islets were isolated from 2 cadaveric donors and divided into 3 groups each for a total of 18 samples. Group one (n = 3) was treated with autologous sera, group two (n = 3) with allogeneic sera, and group three (n = 3) with type 1 diabetic sera (T1DM). Each group was treated for 3 hours at 37 degrees C. Islets were washed, lysed using TRI reagent, and mRNA was isolated using the Total Prep mRNA isolation kit. Isolated cRNA was used for microarray analysis using Illumina Gene Chips Hu6_v2. GeneSpring GX software was used for statistical analysis. Results were significant at P < .05. RESULTS: One-way ANOVA statistical analysis of the microarray data revealed that interleukin-11 (IL-11), interleukin-12A (IL-12A), and Ras related associated with diabetes (RRAD) were overexpressed in islets exposed to diabetic sera when normalized to autologous control (P < .01). Under the same conditions, islet cells exposed to T1DM serum had down-regulation of IL-1 receptor antagonist (IL-1RN). CONCLUSION: These findings suggested that T1DM serum elicited an adaptive and innate immune response to the transplanted islet mass making them more susceptible to cytokine-mediated destruction.


Subject(s)
Blood , Gene Expression Profiling , Inflammation/physiopathology , Islets of Langerhans/physiology , Analysis of Variance , Cadaver , Diabetes Mellitus, Type 1/blood , Humans , Inflammation/genetics , Interleukin-11/genetics , Interleukin-12/genetics , Islets of Langerhans/physiopathology , Oligonucleotide Array Sequence Analysis , Polymerase Chain Reaction , Tissue Donors , Transplantation, Homologous , ras Proteins/genetics
7.
Eur J Dent Educ ; 11(3): 168-76, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17640261

ABSTRACT

AIM: To explore qualitatively the role of gender, ethnicity and clinical experience upon dental students' interpersonal skills when interacting with dental nurses. METHOD: A convenience sample of 15 clinical dental students studying at Belfast (n = 9) and Leeds (n = 6) were invited to take part. The students were interviewed individually using an open format. Interviewing was stopped after 15 interviews as stability and saturation of the qualitative data had occurred. The data were analysed using content analysis. RESULTS: Interactions with dental nurses were primarily dictated by the dental students' perceptions of the essential qualities of a dental nurse. Novitiate students perceived the dental nurse as an 'teacher-ally', whereas clinically experienced students used the nurse as a 'helper'. The degree to which dental students embraced hierarchical working styles and professional demarcation was influenced by clinical experience and gender, ethnicity. In order to promote cooperative working when interacting with dental nurses it seemed there was a need to consider incorporating interprofessional and cultural diversity training into undergraduate programmes. CONCLUSIONS: The dental students' interpersonal skills were affected by clinical experience, gender and ethnicity.


Subject(s)
Clinical Competence , Dental Assistants , Ethnicity , Interprofessional Relations , Students, Dental , Attitude , Attitude of Health Personnel , Communication , Cooperative Behavior , Cultural Diversity , Education, Dental , England , Female , Humans , Interpersonal Relations , Ireland , Male , Sex Factors
8.
Br Dent J ; 202(2): 91-6, 2007 Jan 27.
Article in English | MEDLINE | ID: mdl-17255993

ABSTRACT

AIM: To examine the influence of dental students' gender and ethnicity on their perceptions of dental nurses' duties and upon their communication and working styles when interacting with dental nurses (DNs). METHOD: A survey of clinical dental students attending Queen's University Belfast and University of Leeds. Students were invited to complete the 34 item Communication and Working Styles Questionnaire. The questionnaire assessed the students' perceptions of the duties of a DN and the students' communication and working styles. Factor analysis revealed two communication and working styles which were friendly and difficult styles, respectively. RESULTS: Two hundred and forty-eight students participated giving a response rate of 88%: 58% were female and 30% of students from Leeds were from various ethnic minority groups. The students' perceptions as to the duties of a DN were affected by university attended and ethnicity. The majority of students used friendly communication styles. The type of style used was determined by university attended, gender and ethnicity. Male students had higher mean scores for friendly working styles whereas students from minority ethnic groups had higher mean scores for gender-related communication style. Female students and students from minority ethnic groups had higher mean scores for items relating to teamwork. CONCLUSIONS: This survey illustrates the different communication and working styles used by male and female and dental students from different ethnic backgrounds when interacting and working with DNs.


Subject(s)
Dental Assistants/psychology , Education, Dental/methods , Interprofessional Relations , Students, Dental/psychology , Adult , Analysis of Variance , Chi-Square Distribution , Communication , Ethnicity , Female , Gender Identity , Humans , Male , Sex Factors , Surveys and Questionnaires , Work/psychology
9.
Biotechnol Bioeng ; 93(4): 674-86, 2006 Mar 05.
Article in English | MEDLINE | ID: mdl-16395718

ABSTRACT

A pilot scale whole cell process was developed for the enantioselective 1,2-reduction of prochiral alpha,beta-unsaturated ketone to (R) allylic alcohol using Candida chilensis. Initial development showed high enantiomeric excess (EE > 95%) but low product yield (10%). Process development, using a combination of statistically designed screening and optimization experiments, improved the desired alcohol yield to 90%. The fermentation growth stage, particularly medium composition and growth pH, had a significant impact on the bioconversion while process characterization identified diverse challenges including the presence of multiple enzymes, substrate/product toxicity, and biphasic cellular morphology. Manipulating the fermentation media allowed control of the whole cell morphology to a predominantly unicellular broth, away from the viscous pseudohyphae, which were detrimental to the bioconversion. The activity of a competing enzyme, which produced the undesired saturated ketone and (R) saturated alcohol, was minimized to < or =5% by controlling the reaction pH, temperature, substrate concentration, and biomass level. Despite the toxicity effects limiting the volumetric productivity, a reproducible and scaleable process was demonstrated at pilot scale with high enantioselectivity (EE > 95%) and overall yield greater than 80%. This was the preferred route compared to a partially purified process using ultra centrifugation, which led to improved volumetric productivity but reduced yield (g/day). The whole cell approach proved to be a valuable alternative to chemical reduction routes, as an intermediate step for the asymmetric synthesis of an integrin receptor antagonist for the inhibition of bone resorption and treatment of osteoporosis.


Subject(s)
Candida/metabolism , Heptanol/analogs & derivatives , Ketones/metabolism , Propanols/metabolism , Biotransformation , Fermentation , Industrial Microbiology/methods , Integrin alphaVbeta3/antagonists & inhibitors , Ketones/chemistry , Oxidation-Reduction , Pilot Projects , Stereoisomerism
10.
Brain Res ; 408(1-2): 349-52, 1987 Apr 07.
Article in English | MEDLINE | ID: mdl-3594225

ABSTRACT

Several lines of evidence suggest that cells within the immediate vicinity of the median raphe nucleus may exert an inhibitory influence on locomotor activity. If this theory were correct, one would expect that excitation of neurons within the median raphe would have a suppressive effect on behavior. This possibility was examined in the present study where low doses of the glutamate analogue kainic acid were injected into the median raphe nucleus of methylphenidate-pretreated rats. Our results indicate that these injections were able to antagonize, in a dose-dependent manner, both the horizontal locomotor activity and the nose poking induced by methylphenidate. These results provide further support for the existence of inhibitory median raphe influences on locomotion and suggest the possibility that endogenous excitatory amino acids may play a role in raphe functioning.


Subject(s)
Kainic Acid/pharmacology , Motor Activity/drug effects , Raphe Nuclei/drug effects , Animals , Male , Methylphenidate/pharmacology , Raphe Nuclei/physiology , Rats , Rats, Inbred Strains
11.
Brain Res ; 311(2): 333-41, 1984 Oct 08.
Article in English | MEDLINE | ID: mdl-6208972

ABSTRACT

Stress-induced changes in renin and prolactin secretion were studied using a conditioned emotional response paradigm. Three minutes after being placed in a chamber, the stressed animals received a brief electric shock (1.0 mA for 10 s through the grid floor), then were returned to their home cage. This procedure was repeated for 3 consecutive days. On the fourth day, the rats were placed in the chamber for 3 min, but instead of receiving shock, they were removed and sacrificed. Control animals were treated in the same manner, except that they never received foot shock. The sham-operated stressed rats evidenced significant elevations in plasma renin activity (270%) and prolactin level (550%). Electrolytic lesions in the dorsal raphe nucleus blocked the stress-induced increase in plasma renin activity but did not affect the stress-induced increase in prolactin secretion. Electrolytic lesions in the median raphe nucleus did not affect prolactin levels in either control or stressed animals. However, median raphe lesions led to a significant increase in plasma renin activity in non-stressed rats and potentiated the stress-induced elevation in plasma renin activity. These results suggest that neurons within the dorsal and median raphe nuclei are involved in the regulation of renin but not prolactin secretion during stress. The results also suggest that median raphe neurons play a role in basal renin secretion.


Subject(s)
Mesencephalon/physiopathology , Prolactin/metabolism , Raphe Nuclei/physiopathology , Renin/metabolism , Stress, Psychological/physiopathology , Animals , Caudate Nucleus/analysis , Electroshock , Hippocampus/analysis , Humans , Hydroxyindoleacetic Acid/analysis , Male , Prolactin/blood , Putamen/analysis , Raphe Nuclei/physiology , Rats , Rats, Inbred Strains , Renin/blood , Serotonin/analysis
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