Groups HM Research Articles

Effects of Different Auditory Environments on Behavior, Learning Ability, and Fearfulness in 4-Week-Old Laying Hen Chicks.

Environmental enrichment can improve animal welfare. As a method of environmental enrichment, the effect of different auditory stimulations on the behavior response and welfare of laying hen chicks has yet to be investigated. Therefore, this study was aimed at exploring the impact of various auditory exposures on the behavior, learning ability, and fear response of 4-week-old laying hen chicks. A total of 600 1-day-old chicks were randomly assigned to five different groups: C (control group), LM (Mozart's String Quartets, 65 to 75 dB), LN (recorded ventilation fans and machinery, 65 to 75 dB), HN (recorded ventilation fans and machinery, 85 to 95 dB), and HM (Mozart's String Quartets, 85 to 95 dB). The experiment was conducted from day 1 until the end of the experiment on day 28. Groups LM and LN were exposed to music and noise stimulation ranging from 65 to 75 dB. Groups HN and HM, meanwhile, received noise and music stimulation ranging from 85 to 95 dB. The control group (C) did not receive any additional auditory stimuli. During the experimental period, continuous behavioral recordings were made of each group of chicks from day 22 to day 28. On day 21, the PAL (one-trial passive avoidance learning) task was conducted. On days 23 and 24, OF (open field) and TI (tonic immobility) tests were performed, and the levels of serum CORT (corticosterone) and DA (dopamine) were measured. The results indicated that exposure to music and noise at intensities ranging from 85 to 95 dB could reduce comforting, preening, PAL avoidance rate, the total number of steps and grid crossings of OF, and the concentration of DA in 4 WOA chicks (p < 0.05), increase the freezing times of OF (p < 0.05); 65 to 75 dB of noise stimulation could reduce preening and total number steps of OF in 4 WOA chicks (p < 0.05), increase the freezing times of OF (p < 0.05); and 65 to 75 dB of music exposure could reduce the concentration of CORT in 4 WOA chicks (p < 0.05). Therefore, 65 to 75 dB of music exposure could produce positive effects on chicks and showed relatively low CORT level, whereas 85 to 95 dB of music and noise exposure could reduce comforting and preening behavior, impair learning ability, and increase the fear responses of chicks.

Evaluation of the flexural strength of metal frameworks fabricated by sintering-based computer-aided manufacturing methods

Statement of problemSintering-based computer-aided metal manufacturing strategies have been proposed as an alternative to hard metal milling. While these fabrication methods have been evaluated in terms of marginal and internal discrepancies and bond strength to porcelain, limited information on metal frameworks is available regarding their flexural yield strength. PurposeThe purpose of this in vitro study was to evaluate the flexural yield strength of 3-unit cobalt-chromium (Co-Cr) metal frameworks fabricated by hard metal milling (HMM), presintered soft metal milling (PSMM), and direct metal laser melting (DMLM) with 25-μm and 50-μm layer thicknesses. Material and methodsThree-unit master metal die models were prepared. A total of 40 metal frameworks (n=10) were fabricated by using HMM (group HM), PSMM (group PSM), and DMLM with 25-μm (group LM25) and 50-μm layer thicknesses (group LM50). Metal frameworks were cemented to the master die and then subjected to a 3-point bend test. The flexural yield force was used to calculate the flexural yield strength. The data were statistically analyzed (α=.05). One metal framework from each group was evaluated with scanning electron microscopy for microstructural analysis. ResultsThe group LM50 exhibited the lowest significant (P<.001) flexural yield strength values. The group HM exhibited higher flexural yield strength values than the other groups. No significant difference was found between the groups LM25 and PSM (P=.954) or between the groups PSM and HM (P=.111). ConclusionsThe fabrication method significantly affected the flexural yield strength of metal frameworks. Metal frameworks fabricated by DMLM with a 50-μm layer thickness exhibited considerably lower flexural yield strength values.

Effects of silibinin-loaded thermosensitive liposome-microbubble complex on inhibiting rabbit liver VX2 tumors in sub-hyperthermia fields.

In the present study, the effects of silibinin-loaded thermosensitive liposome-microbubble complex (STLMC) on rabbit liver VX2 tumors in sub-hyperthermia fields were investigated using two-dimensional ultrasonography (2D US), contrast-enhanced US (CEUS), hematoxylin and eosin (H&E) staining, immunohistochemistry and ultrastructure observation. 50 rabbits with VX2 liver tumors were divided into five groups: Sub-hyperthermia microwave ablation group (SHM), STLMC injection group (STLMC), SHM ablation plus STLMC injection group (SHM + STLMC), microbubble injection group and blank control group without any treatment. Rabbits in each group were examined using 2D US and CEUS in order to evaluate the tumor volume and diameter before treatment and at day 7 and 21 after treatment. Morphology, expression of CD163 and CD206, and ultrastructure of the tumors were assessed. The average post-treatment volume of tumors in group SHM + STLMC was 1.17±0.88 cm3 at day 7 and 2.15±0.96 cm3 at day 21, which was significantly decreased compared with all other groups (P<0.05). H&E staining indicated that the number of disordered macrophages in the SHM + STLMC group significantly increased compared with the other groups (P<0.05). Immunohistochemical results demonstrated that in the SHM + STLMC, the expression of CD163 and CD206 significantly decreased compared with all other groups (P<0.05). These results suggested that STLMC has a potential function in preventing tumor growth, which may be due to its inhibitory effect on tumor-associated macrophages in the tumor microenvironment.

Shear bond strength of ceramic and metallic orthodontic brackets bonded with self-etching primer and conventional bonding adhesives.

IntroductionAdult patients typically require high-quality orthodontic treatment for ceramic brackets, but some clinicians remain concerned about the bond strength of these brackets. Therefore, the aim of this study was to determine the shear bond strength and de-bonding characteristics of metallic and ceramic brackets bonded with two types of bonding agents.MethodsIn an experimental study done in 2013 in Babol, Iran, 120 extracted human maxillary premolar teeth were randomly divided into four groups as follows: HM group: metallic bracket/conventional bonding agent; SM group: metallic bracket/Transbond self-etching primer; HC group: ceramic bracket/conventional bonding agent; SC group: ceramic bracket/Transbond self-etching primer. Twenty-four hours after thermocycling (1000 cycle, 5 °C–55 °C), the shear bond strength values were measured. The amount of resin remaining on the tooth surface (adhesive remnant index: ARI) was determined under a stereomicroscope. Enamel detachment index was evaluated under a scanning electron microscope. To perform statistical analysis, ANOVA, Kruskal–Wallis, and Tukey post-hoc tests were applied. The level of significance was set at p <0.05.ResultsThe mean shear bond strength values (MPa ± SD) were group HM=12.59, group SM=11.15, group HC=7.7, and group SC=7.41. Bond strength differences between groups HM and SM (p=0.063) and between HC and SC (p=0.091) were not statistically significant. There were significant differences between HM and HC and between SM and SC groups (p < 0.05). Insignificant differences were found in ARI among all groups.ConclusionOur findings indicated that the metallic brackets had higher bond strengths in comparison with ceramic brackets. In addition, self-etching primer was able to produce fewer bonds compared with the conventional technique. Many samples showed the bracket-adhesive interface failure or failure inside the adhesive.

Biochemical and immunological responses of young turkeys to vaccination against Ornithobacterium rhinotraheale and different levels of dietary methionine

The objective of this study was to verify the hypothesis that increasing levels of dietary methionine can stimulate the mechanisms of cell-mediated and humoral immunity in young turkeys. The blood and organs involved in cell-mediated and humoral immune responses were analyzed in 8-week-old turkeys that had been vaccinated against Ornithobacterium rhinotraheale (ORT) infection (on days 17 and 48). The birds were fed diets with a low (LM), medium (MM) and high (HM) methionine content (0.45 and 0.40%, 0.60 and 0.51%, 0.71 and 0.57% in weeks 1 - 4 and 5 - 8, respectively). Dietary methionine supplementation led to a significant increase in body weights of turkeys at 56 days of age, from 3532 g in group LM to 3720 g in group MM and 3760 g in group HM (p=0.001). A significant increase in vaccine-induced antibody titers against ORT was noted in group HM relative to group LM (p=0.006). Increasing levels of methionine had no significant effect on total serum IgG nor IgM levels and most serum biochemical parameters, TP, ALB, GLOB, GLU, AST, ALP, P and Ca. In comparison with group LM, group HM turkeys were characterized by a lower percentage of IgM⁺ B cell subpopulation in the blood and bursa of Fabricius. The percentages of CD4⁺ and CD8⁺ T cell subpopulations in the bursa of Fabricius in group HM were significantly different from those found in groups LM and MM. The highest percentages of CD4⁺ T cells and CD8⁺ T cells in the spleen were observed in groups LM (p<0.001) and HM (p=0.04), respectively. The differences were statistically significant relative to the remaining groups. Turkeys of group LM were characterized by a lower CD4⁺ T cell percentage in the thymus (p<0.001) and a lower CD8⁺ T cell percentage in the cecal tonsils (CTs) (p<0.01). Vaccination against ORT resulted in a significant increase in the percentage of CD4⁺CD8⁺ T cell subpopulation and a decrease in the percentage of CD8⁺ T cell subset in the spleen.

Segal–Bargmann transform and Paley–Wiener theorems on Heisenberg motion groups

AbstractWe consider the Heisenberg motion groups ℍ𝕄 = ℍ

Admissibility of Local Systems for some Classes of Line Arrangements

AbstractLet 𝒜 be a line arrangement in the complex projective plane ℙ2 and let M be its complement. A rank one local system 𝓛 on M is admissible if, roughly speaking, the cohomology groups Hm(M, 𝓛) can be computed directly from the cohomology algebra H*(M, ℂ). In this work, we give a sufficient condition for the admissibility of all rank one local systems on M. As a result, we obtain some properties of the characteristic variety 𝒱1(M) and the Resonance variety 𝓡1(M).

Effect of volume therapy with 6 ％ hydroxyethyl starch 130/0.4 on mesenteric microcirculation in a rabbit model of hypovolemia

Objective To investigate the effect of volume therapy with 6％ hydroxyethyl starch (HES) 130/0.4 on mesenteric microcirculation in a rabbit model of hypovolemia.Methods Sixty-four adult male rabbits,weighing 2.0-2.3 kg,were randomly divided into 4 groups( n =16 each):control group (group C),hypovolemia group (group HM),Ringer's solution group (group RS) and 6％ HES 130/0.4 group (group HES).The animals were anesthetized with sodiun pentobarbital 3.0-3.5 mg/kg.Femoral artery,femoral vein and right internal jugular vein were cannulated for MAP monitoring,blood withdrawing and fluid adminstration.Hypovolemia was induced by withdrawing blood from femoral vein of 30％ blood volume in 30 min in groups HM,RS and HES.In group C,no blood was withdrawed.In group RS,Ringer's solution 3 times of the volume of blood withdrawn was infused,while 6％ HES 130/0.4 equal volume of blood withdrawn was infused via right internal jugular vein immediately at the end of blood withdrawing.MAP and HR were recorded and femoral artery and femoral vein blood samples were taken before blood withdrawing (T0),immediately at the end of blood withdrawing(T1 ),immediately at the end of volume therapy(T2 ) and 30 min after volume therapy(T3 ).DO2,VO2 and ERO2 were calculated.Diameter and blood flow speed of microvessel were determined.Results Compared with group C,HR was significantly increased,MAP decreased,diameter and blood flow speed of microvessel were decreased at T1～3,DO2 was increased at T1 in group HM.Compared with group HM,MAP was significantly increased at T2,HR decreased at T2,3,DO2and VO2 were increased at T1～3,diameter of arteriole was increased at T2 whlie decreased at T3,diameter of veinule and blood flow speed of microvessel were increased at T2,3 in group RS,MAP was significantly increased at T2,HR was decreased whlie DO2 and VO2 were decreased,VO2,ERO2,diameter and blood flow speed of microvessel were increased at T2,3 in group HES.Compared with group RS,DO2,VO2 and ERO2 were significantly decreased at T3 in group HES.Conclusion Volume therapy with 6％ HES 130/0.4 can improve mesenteric microcirculation,organ perfusion and oxygen metabolic in a rabbit model of hypovolemia. Key words: Hetastarch ; Fluid therapy ; Hypovolemia; Microcirculation

Magnesium Sulfate Prevents Remifentanil-Induced Postoperative Hyperalgesia in Patients Undergoing Thyroidectomy

In a randomized, double-blind, prospective study, we investigated whether an intraoperative high versus low dose of remifentanil increased postoperative hyperalgesia and whether magnesium can prevent remifentanil-induced hyperalgesia. Ninety patients undergoing thyroidectomy were randomly assigned to 1 of 3 groups. Remifentanil was intraoperatively infused at 0.05 μg/kg/min (group LO) or 0.2 μg/kg/min (groups HI and HM). Patients in group HM received MgSO(4) 30 mg/kg at induction followed by an intraoperative infusion of 10 mg/kg/h. Mechanical pain thresholds on the forearm and periincisional area were assessed by von Frey filament the evening before surgery and postoperatively at 24 and 48 hours. Pain measured on a verbal numerical rating scale (VNRS) (0-10) and additional analgesics were recorded in the postanesthesia care unit postoperatively at 6, 24, and 48 hours. There was a significantly greater decrease in pain threshold on the periincisional area at 24 and 48 hours postoperatively in group HI, as compared with the other 2 groups. The 95% confidence intervals for the mean difference in pain thresholds on the periincisional area at 24 and 48 hours postoperatively were 0.31 to 1.11 and 0.36 to 1.14 for group HI versus group LO, 0.45 to 1.26 and 0.54 to 1.32 for group HI versus group HM (values are log(10) of force in milligrams). The change in pain threshold on the forearm was similar among the groups. Group HI had significantly higher VNRS scores (median [interquartile range], 3 [2-4]) than group LO (2 [1-3] and group HM (2 [1-3]) at 48 hours postoperatively. The 95% confidence intervals for median difference in VNRS score at 48 hours postoperatively were 1 to 2 for group HI versus group LO and 0 to 2 for group HI versus group HM. There were no significant differences in the number of patients who requested rescue analgesics in the postoperative anesthesia care unit and general ward during 48 hours postoperatively among the 3 groups. A relatively high dose of intraoperative remifentanil enhances periincisional hyperalgesia. Intraoperative MgSO(4) prevents remifentanil-induced hyperalgesia. However, hyperalgesia did not reach clinical relevance in terms of postoperative pain or analgesic consumption in patients undergoing thyroidectomy.

Testing of Antitumor Effects of Hypericum Perforatum L. and Hypericum Maculatum C. in Ehrlich Ascite in Swiss Mice

Hypericum perforatum L or St. John's wort is a medicinal plant with long history use in traditional. Because Romanian and European Pharmacopoeia accept as officinal only H. perforatum L, the present study compare the characteristics of the H. perforatum and H. maculatum. The experiment was carried out on 28 white Swiss male mice, for 14 days long; each animal received 106 Ehrlich Ascitic Carcinoma cells i.p., in the day 0. Animals were divided in four equal experimental groups, First group (HM) received 172 mg/kg b.w. H. maculatum, the second group (HP) 172 mg/kg b.w. H. perforatum, the control group, and the last group Doxorubicin cloride 2.5 mg/ kg b.w in day 6 of experiment. Both groups HM and HP received intra peritoneal injections in days 1, 4, and 7 of experiment. White blood cells and the platelets were increase in Hypericum treated groups; leucocytosis was more evident in H. perforatum, mainly because of the granulocytes. Doxorubicin prevents the elevation of granulocytes levels, no similar effect was found in Hypericum treated animals. Even no so effective like Doxorubicin, alcoholic extracts provides a protective effect, but statistical significance was found only for H. maculatum. In conclusion, both Hypericum sp. (H. maculatum and H. perforatum), have shown anticancer effect, through inhibition of tumor cells development and elevating the white blood cells level. This might be the basis of new pharmaceutical remedies using H.maculatum a wide spread species in mountain regions of Romania.

Description of outcomes of experimental infection with feline haemoplasmas: Copy numbers, haematology, Coombs’ testing and blood glucose concentrations

The aim of this study was to compare blood copy, haematological and glucose values between cats experimentally infected with either Mycoplasma haemofelis (Group HF: 10 cats), ‘Candidatus M. haemominutum’ (Group HM: 3 cats) or ‘Candidatus M. turicensis’ (Group TU: 3 cats). Blood samples were collected regularly up to 85 days post-infection (DPI) for haemoplasma real-time quantitative PCR, haematology, Coombs’ testing and blood glucose measurement. Statistical analysis was performed using a general linear model (ANOVA) appropriate for a repeated measures experiment with significance set as P<0.05. Cats in Group TU had significantly lower blood copy numbers than cats in Group HF (P<0.001) and HM (P<0.001). All Group HF cats developed anaemia (often severe), macrocytosis and evidence of erythrocyte-bound antibodies whereas Groups HM and TU cats did not. Group HF had significantly lower PCVs, haemoglobin concentrations and red blood cell counts, and significantly higher mean cell volumes, than Groups HM and TU. In Group HF, erythrocyte-bound antibodies reactive at 4°C (both IgM and IgG) appeared between 8 and 22 DPI and persisted for two to four weeks, whereas those reactive at 37°C (primarily IgG) appeared between 22 and 29 DPI and persisted for one to five weeks. In most cats antibodies appeared after the fall in haemoglobin started. Although Group TU had significantly lower glucose concentrations than Groups HF (P=0.006) and HM (P=0.027), mean blood glucose concentrations remained within the reference range in all groups. This study demonstrates that M. haemofelis infection, in contrast to ‘Candidatus M. haemominutum’ and ‘Candidatus M. turicensis’ infection, can result in a severe macrocytic anaemia and the development of cold and warm reactive erythrocyte-bound antibodies.

Homotheties of cylindrically symmetric static manifolds and their global extension

Cylindrically symmetric static manifolds are classified according to their homotheties and metrics. In each case the homothety vector fields and the corresponding metrics are obtained explicitly by solving the homothety equations. It turns out that these metrics admit homothety groups Hm, where m = 4,5,7,11. This classification is then used to identify the cylindrically symmetric static spaces admitting the local homotheties, which are globally prohibited due to their topological construction. Einstein's field equations are then used to identify the physical nature of the spaces thus obtained.

Alterations in the arrhythmogenic dose of epinephrine after xylazine or medetomidine administration in halothane-anesthetized dogs

Summary Eight dogs (12.5 to 21.5 kg) were assigned at random to each of 3 groups that were not given glycopyrrolate (hs, hx, hm) and to each of 3 groups that were given glycopyrrolate (hgs, hgx, hgm). Dogs were anesthetized with halothane (1.31% end-tidal concentration), and ventilation was controlled (PCO2 35 to 40 mm of Hg end-tidal concentration). Glycopyrrolate was administered iv and im at a dosage of 11 μg/kg of body weight, each. Saline solution, xylazine (1.1 mg/kg, im, or medetomidine (15 μg/ kg, im) was administered 10 minutes after baseline arrhythmogenic dose of epinephrine (ade) determination. Redetermination of the ade at the same infusion rate was started 10 minutes after drug administration. Arrhythmogenic dose was determined by constant infusion of epinephrine at rates of 1.0 and 2.5 μg/kg/min. The ade was defined as the total dose of epinephrine inducing at least 4 ectopic ventricular depolarizations within 15 seconds during a 3-minute infusion or within 1 minute after the end of the infusion. Total dose was calculated as the product of infusion rate and time to arrhythmia. Statistical analysis of the differences between baseline ade and posttreatment ade for groups hs, hx, and hm was performed by use of one-way anova. Mean ± sem baseline ade values for groups hs, hx, and hm were 1.50 ± 0.11, 1.49 ± 0.10, and 1.57 ± 0.22 pg/kg, respectively, and for groups hgs, hgx, and hgm were 3.37 ± 0.61, 3.10 ± 0.75, and 3.04 ± 0.94 pg/kg, respectively. Differences for groups hs, hx, and hm were – 0.02 ± 0.15, – 0.00 ± 0.14, and – 0.21 ± 0.17 μg/kg, respectively, and for groups hgs, hgx, and hgm, were – 0.59 ± 0.26, – 0.41 ± 0.15, and – 0.58 ± 0.20 μg/kg, respectively. Differences among groups hs, hx, and hm, or among groups hgs, hgx, and hgm were not significant. We conclude that without and with cholinergic blockade in halothane-anesthetized dogs: preanesthetic dosages of xylazine (1.1 mg/kg, im) or medetomidine (15 μg/kg, im) do not enhance arrhythmogenicity, and at these dosages, there is no difference in the arrhythmogenic potential of either α2-adrenoceptor agonist.

A Preliminary Study of the Milk Production, Bodyweight Changes and Some Blood Characteristics of Underfed Beef Cows

SUMMARY Ten Hereford × Dairy Shorthorn heifers were allocated to three treatments: adequately fed and machine milked (HM); fed to maintenance requirements and machine milked (LM); and fed to maintenance requirements and suckled (LS), for 72 days with 3, 3 and 4 animals respectively. Average daily milk yields showed a decline over the period from 9·8 to 9·0 kg, 9·0 to 5·6 kg and 6·1 to 5·9 kg for groups HM, LM and LS, with corresponding weight changes of o, —57 and —25 kg. Mean milk solid-not-fat (SnF) contents were 9·07 and 8.61 ( P