1
|
Dexmedetomidine protects the uterus against ischemia-reperfusion injury in rats. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2024; 28:2501-2508. [PMID: 38567610 DOI: 10.26355/eurrev_202403_35757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
OBJECTIVE This study aimed to analyze the histopathological and biochemical effects of dexmedetomidine on the rat uteri exposed to experimental ischemia-reperfusion injury. MATERIALS AND METHODS Twenty-four female rats were randomly divided into three groups. Group 1 was defined as the control group. An experimental uterine ischemia-reperfusion model was created in Group 2. Group 3 was assigned as the treatment group. Similar uterine ischemia-reperfusion models were created for the rats in Group 3, and then, unlike the other groups, 100 μg/kg of dexmedetomidine was administered intraperitoneally immediately after the onset of reperfusion. In blood biochemical analysis, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and malondialdehyde (MDA), interleukin 1beta (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) levels were measured. In the histopathological analyses, endometrial epithelial glandular changes (leukocytosis, cell degeneration) and endometrial stromal changes (congestion, edema) were analyzed using the tissue damage scoring system. RESULTS It was observed that IL-1β, IL-6, and TNF-α levels were significantly suppressed in Group 3 compared to Group 2 (p=0.001, p<0.001 and p=0.001, respectively). MDA level was noted as the highest in Group 2. The MDA value in Group 3 was measured at 5.37±0.82, which was significantly decreased compared to Group 2 (p<0.001). An increase in antioxidant enzyme activities (SOD and GSH-PX) was observed in Group 3 compared to Group 2 (p=0.001 and p=0.006, respectively). In our histopathological analysis, a significant improvement in endometrial epithelial glandular and endometrial stromal changes was revealed in Group 3 compared to Group 2 (p<0.001). CONCLUSIONS In our study, it has been documented that dexmedetomidine protects the uterine tissue against ischemia-reperfusion injury.
Collapse
|
2
|
Mechanical Properties of Zirconia Materials with Different Translucency: An In Vitro Study. INT J PROSTHODONT 2024; 37:72-79. [PMID: 38381986 DOI: 10.11607/ijp.8164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
PURPOSE To investigate the biaxial flexural strength of zirconia materials with different translucency before and after aging procedures and to evaluate the effects of aging on hardness and surface characteristics. MATERIALS AND METHODS A total of 90 disc-shaped specimens (n = 30 each) were prepared from translucent (Upcera-ST, Upcera Dental), high translucent (Katana HT, Kuraray Noritake), and ultra high translucent (Katana UTML, Kuraray Noritake) zirconia materials to a ø.16 ±1.2 mm thickness. The different translucency discs were then divided into three subgroups; one group was subjected to aging in a chewing simulator (n = 10), one group was aged with thermocycling (n = 10), and one was a control group (n = 10). Biaxial flexural strength, Vickers hardness, and surface characteristics were examined for all discs. The data were analyzed using the Shapiro-Wilk (P = .05), Mann-Whitney U, and Kruskal-Wallis H tests. Fracture strength was determined using biaxial bending strength tests, and Weibull analysis was used to analyze the resulting data. RESULTS A statistically significant difference was found among zirconia materials with different translucency in terms of fracture strength. On average, fracture strength was highest in the Upcera ST group (1,932.87 MPa) and lowest in the Katana UTML group (1,073.6 MPa; P = .001). The results of Weibull analysis showed a statistically similar distribution for all groups. CONCLUSIONS Aging procedures did not cause significant differences in fracture strength and hardness. The fracture strength of the zirconia materials with different translucency was considered acceptable for intraoral use.
Collapse
|
3
|
The effects of metformin on the bone filling ration around of TiAl 6Va 4 implants in non diabetic rats. J Oral Biol Craniofac Res 2020; 10:474-477. [PMID: 32904211 DOI: 10.1016/j.jobcr.2020.07.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/15/2020] [Accepted: 07/19/2020] [Indexed: 12/12/2022] Open
Abstract
Objectives In this research it was aimed to that evaluation of the effects of systemic metformin administration on the periimplant bone tissue response of TiAl6Va4 implants in experimental rat model. Materials and method Firstly TiAl6Va4 implants were inserted surgically in the metaphyseal part of the tibial bone and after, the rats were randomly separated into two groups: Controls (CNT) (n = 10) and Metformin group (M) (n = 10). No additional treatment was applied to the controls during the 4-week experimental period. Rats received 40 mg/kg metformin in every day during the four week experimental period in M group. At the end of the 28-day follow-up period, the TiAl6Va4 implants with surrounding bone were used for the histopathologic analysis. To analysis of the datas between M and CNT Student-T Test was used. Result Periimplant bone tissue filling ratios (%) were detected higher in M group compared with the CNT (P < 0.05). Conclusion Systemic administration of metformin may increases titanium implant osseointegration in non-diabetic rats.
Collapse
|
4
|
Effect of Application Time of Two Different Disinfectants on the Surface Roughness of an Elastomeric Impression Material. J Clin Diagn Res 2020. [DOI: 10.7860/jcdr/2020/44752.13828] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Introduction: Pathogens, such as cytomegalovirus, hepatitis B virus, hepatitis C virus, herpes simplex virus types 1 and 2, and human immunodeficiency virus are transmitted, threatening the health of dental laboratory workers, especially as a result of saliva and blood contact of patients. To prevent cross-infection, impression materials should be disinfected at the end of the impression process in the mouth. Aim: To study the effect of application time of sodium hypochlorite and quaternary ammonium-based disinfectant solution on the surface roughness of an elastomeric impression material. Materials and Methods: In this in-vitro study done during March 2020, 10 disc-shaped samples were used in each group, with a total of 110 samples obtained from a light body elastomeric impression material with dimensions of 15×3 mm. The samples were kept in a sodium hypochlorite solution (Wizard; Rehber Kimya, Istanbul, Turkey) at concentrations of 1% and 5% for 1, 5, 10, and 30 minutes and in a quaternary ammonium-based disinfectant (Zeta 7 Solution, Zhermack SpA, Italy) for 10 and 30 minutes. Surface roughness measurements were taken with a profilometer device. The data obtained were statistically analysed by Kolmogorov-Smirnov test and Wilcoxon signed rank test for dependent/paired groups for the continuous data. The significance level was set to α=0.05. Results: A statistically significant difference was found between the control group and the 1% sodium hypochlorite (30 min p-value 0.037), and 5% sodium hypochlorite (30 min p-value 0.017). The statistical evaluation of the surface roughness of the samples with different concentrations of sodium hypochlorite and the same times was done and found statistically significant at 30 mins, p-value 0.021. Conclusion: The prolonged application of the sodium hypochlorite disinfectant at 1% and 5% concentrations caused a significant increase in the light body elastomeric impression material’s surface roughness
Collapse
|
5
|
Evaluation of the accuracy of the mechanical torque wrench by the number of uses and ratchet type. AMERICAN JOURNAL OF DENTISTRY 2019; 32:251-254. [PMID: 31675194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
PURPOSE To evaluate the accuracy of mechanical torque rachet types based on the number of uses. METHODS A total of 25 ratchets, including three frictional- and two spring-type torque ratchets from every mechanical torque ratchet group, were used in our study. A digital torque measurement device was used in assessing the efficiency of mechanical torque ratchets. All ratchets were tightened according to the torque values recommended by the companies. The ratchets were tightened 500 times in total. RESULTS Given the changes in torque delivery by the number of uses, a statistically significant torque loss was observed in the Bego ratchets (P< 0.05), and a statistically significant increase was found in the torque values of the other ratchet groups (P< 0.05). The highest increase in torque values was obtained in the MEDENTIKA ratchet group. CLINICAL SIGNIFICANCE This study showed that there are changes in the torque values applied based on the number of rachet uses. Thus, clinicians are advised to regularly evaluate the accuracy of the rachets.
Collapse
|
6
|
The effects of morus nigra on the alveolar bone loss in experimentally-induced periodontitis. Eur Oral Res 2019; 53:99-105. [PMID: 31579889 PMCID: PMC6761488 DOI: 10.26650/eor.20190021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/22/2018] [Accepted: 01/25/2019] [Indexed: 12/28/2022] Open
Abstract
Purpose The aim of this study is to evalute the anti-inflammatory effects of morus migra on experimentally-induced periodontitis in rats. Materials and methods Twenty-four Wistar-albino rats were randomly divided into three groups: control group (C, n=8), experimental periodontitis (PER, n=8), experimental periodontitis and treated with Morus nigra (MN+PER, n=8) (50 mg/kg per day for 21 days). After 21 days, the rats were sacrificed, and alveolar bones were evaluated histopathologically and histometrically analyzed to obtain level of alveolar bone loss. The detection of RANKL and OPG were immunohistochemically performed. Serum and tissue levels of MMP-8 and MMP-13 were also analyzed. Results Morus nigra treatment decreased tissue MMP-8 and MMP-13 levels and there were significant differences in the case of tissue levels of MMP-8 and MMP-13 between groups PER and MN+PER (p=0.035, p=0.041). There were no significant differences among all the groups serum levels of MMP-8 and MMP-13 (p=0.067, p=0.082). In the histometric evaluation, alveolar bone loss was greater in the PER group compared to C and MN groups (p=0.035). Immuno-histochemical staining of RANKL activities were found significantly lower (p=0.037) and OPG activities were found significantly higher in MN+PER group when compared to PER group (p=0.021). Conclusion The present study reveals that systemic administration of Morus nigra significantly inhibited the regional alveolar bone resorption and contributes to periodontal healing in the rat experimental-periodontitis models.
Collapse
|
7
|
Spectrophotometric Evaluation of Anterior Maxillary Tooth Color Distribution According to Age and Gender. J Prosthodont 2018. [PMID: 29533497 DOI: 10.1111/jopr.12783] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
PURPOSE To determine the effects of age and gender on the color distribution of the right maxillary central, lateral incisors, and canine teeth. MATERIALS AND METHODS The tooth color was measured using the VITA Easyshade V spectrophotometer with a total of 202 volunteers (89 men, 113 women). The age distribution in this study was between 15 and 70 years old (average: 31). A grey background color was used to prevent background reflection while performing the color measurements. RESULTS According to the VITAPAN Classical shade guide, the tooth color distribution of the central and lateral incisors showed a maximum of A2, with a maximum of B3 for the canine teeth. When comparing the International Commission on Illumination L* , a* , and b* values (CIELab color space coordinates) of the teeth with subject gender, statistically significant differences were not found between gender and the L* and b* values (p > 0.05); however, a statistically significant difference was observed between gender and the a* values (p < 0.05). CONCLUSION When the distribution ratio of tooth color was examined, different ratios were determined based on gender and age and between the maxillary central, lateral incisors, and canine teeth. A uniform tooth color should not be chosen for anterior restorations, and factors such as gender and age should be considered when making a color selection for patients.
Collapse
|
8
|
Is there a relation between dental anxiety, fear and general psychological status? PeerJ 2017; 5:e2978. [PMID: 28229019 PMCID: PMC5314953 DOI: 10.7717/peerj.2978] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 01/10/2017] [Indexed: 11/20/2022] Open
Abstract
Background Dental anxiety is a widespread problem in many populations. This problem can be a barrier to dental care and may lead to poor oral health. Dental anxiety may be related to psychological status. Aims The aim of the present study was to assess the levels of dental anxiety, dental fear, Beck Depression, and state-trait anxiety according to age, gender and education level in patients at the periodontology clinic in the Diyarbakır Mouth and Dental Health Center. Study Design A total of 231 patients (115 males, 116 females) filled out dental fear scale (DFS), dental anxiety scale (DAS), Beck Depression Inventory (BDI), state-trait anxiety inventory-state (STAI-S), and state-trait anxiety inventory–trait (STAI-T) questionnaires, and evaluations of DFS, DAS, BDI, STAI-S, and STAI-T were conducted according to age, gender, and education level. Results The mean DFS, DAS, BDI, STAI-T, and STAI –S were 45.64, 9.15, 13.16, 38.90, and 40.18, respectively. There was a significant association among DFS, DAS, BDI, STAI-S, and STAI-T (p < 0.05). These surveys scores were significantly higher in females than males (p < 0.05). The results of this study indicated that gender age and education level have important effects on DFS, DAS, BDI, STAI-S, and STAI-T (p < 0.05). Conclusion Dental anxiety and dental fear were found to be related to psychological status (BDI, STAI-S, and STAI-T) over time. There are some patients with unaddressed psychological distress.
Collapse
|
9
|
Measuring the resistance of different substructure materials by sticking them to dentine with two different resin cements in vitro. Niger J Clin Pract 2016; 19:730-736. [PMID: 27811443 DOI: 10.4103/1119-3077.164339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION The resistance of three different substructure materials - metal (Cr-Co), zirconium (Zr), and ceramics (IPS Empress II) - was measured by sticking them to dentine with two different resin cements, a dual-cure resin cement (Panavia F 2.0 Light) and a self-adhesive resin cement (BisCem). MATERIALS AND METHODS In an in vitro study, 72 central upper front teeth were selected with no decay or apparent breakage and with complete development, removed for periodontal reasons. Labial and incisal surfaces of all teeth were prepared. Molds were obtained to prepare metal (Co-Cr), Zr, and ceramic (IPS Empress II) blocks for use in the study. The compressive strengths of the obtained material infrastructures were examined after thermal cycle processing by performing cementation to the teeth with two different cements. The data obtained were analyzed statistically. The Mann-Whitney U-test was used for comparisons of the groups with two options, and Kruskal-Wallis variance analysis was used to compare more than two groups. P<0.05 were considered statistically significant. RESULTS While the highest result between samples was 117.86 ± 47.94 N in the dual-cure (Panavia)-ceramic group, the lowest value was observed at 6.53 ± 3.12 N in the self-adhesive (BisCem)-metal group. There was a significant difference between dual-cure (Panavia) and self-adhesive (BisCem) groups. CONCLUSION In this study, we measured the bond strength; our most durable resistance groups were found to be, in order, Panavia-ceramics >Panavia-metal >Panavia-Zr >self-adhesive-ceramics >self-adhesive-Zr >and self-adhesive-metal.
Collapse
|
10
|
Evaluation and comparison of the marginal adaptation of two different substructure materials. J Adv Prosthodont 2015; 7:257-63. [PMID: 26140178 PMCID: PMC4486622 DOI: 10.4047/jap.2015.7.3.257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/16/2015] [Accepted: 04/07/2015] [Indexed: 11/25/2022] Open
Abstract
PURPOSE In this study, we aimed to evaluate the amount of marginal gap with two different substructure materials using identical margin preparations. MATERIALS AND METHODS Twenty stainless steel models with a chamfer were prepared with a CNC device. Marginal gap measurements of the galvano copings on these stainless steel models and Co-Cr copings obtained by a laser-sintering method were made with a stereomicroscope device before and after the cementation process and surface properties were evaluated by scanning electron microscopy (SEM). A dependent t-test was used to compare the mean of the two groups for normally distributed data, and two-way variance analysis was used for more than two data sets. Pearson's correlation analysis was also performed to assess relationships between variables. RESULTS According to the results obtained, the marginal gap in the galvano copings before cementation was measured as, on average, 24.47 ± 5.82 µm before and 35.11 ± 6.52 µm after cementation; in the laser-sintered Co-Cr structure, it was, on average, 60.45 ± 8.87 µm before and 69.33 ± 9.03 µm after cementation. A highly significant difference (P<.001) was found in marginal gap measurements of galvano copings and a significant difference (P<.05) was found in marginal gap measurements of the laser-sintered Co-Cr copings. According to the SEM examination, surface properties of laser sintered Co-Cr copings showed rougher structure than galvano copings. The galvano copings showed a very smooth surface. CONCLUSION Marginal gaps values of both groups before and after cementation were within the clinically acceptable level. The smallest marginal gaps occurred with the use of galvano copings.
Collapse
|
11
|
Comparison of the effects of different loading locations on stresses transferred to straight and angled implant-supported zirconia frameworks: a finite element method study. BIOTECHNOL BIOTEC EQ 2015. [DOI: 10.1080/13102818.2015.1028445] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
|
12
|
Prevalence of sleep disturbance in chronic pain. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2014; 18:2475-2481. [PMID: 25268092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE Sleep is a vital function for human beings, which can be affected by several factors. Chronic pain is one of these factors where it is the most frequent cause for seeking medical care in combination with insomnia. The aim of this study is to examine the prevalence and relationship between sleep disturbance and chronic pain. PATIENTS AND METHODS After approval, a total of 85 Family Medicine Units from over 170 in Tokat were randomly selected using a 50% sampling. A sample of 2635 subjects, over the age of 19 years, who were registered with the selected Family Medicine Units, were assessed due to gender, age group, and the urban/rural population size of Tokat using the stratified sampling method. The sample size distribution was calculated as 1515 urban subjects, 1120 rural subjects; 1345 female subjects, 1290 male subjects; 1123 subjects between 20-39 years of age, 1103 subjects between the ages of 40-64, and 409 subjects over 64 years of age. After sampling, subjects were invited to participate in the study via an invitation letter, and agreeing individuals were taken to the Family Medicine Unit for face-to-face meetings. Written, informed consent was obtained, along with demographic data. The presence of chronic pain was recorded. According to the presence of chronic pain, all subjects were separated into two groups as Group Chronic Pain and Group Non-Chronic Pain. The visual analog scale for pain intensity, and Pittsburgh Sleep Quality Index for sleep quality, were performed with all subjects. A multiple linear regression model was used to assess the predictors of sleep quality. Analyses were conducted using the Statistical Package for Social Sciences program (SPSS Inc., Chicago, IL, USA), version 20.0. The statistical significance for all analyses was set at p < 0.05. RESULTS The mean global Pittsburgh Sleep Quality Index score of Group Chronic Pain (5.30 ± 4.29) was significantly higher than in Group Non-Chronic Pain (3.22 ± 3.30; p < 0.01). The mean Pittsburgh Sleep Quality Index scores of females (5.69 ± 4.40) were significantly higher than males (4.54 ± 3.96) in Group Chronic Pain (p = 0.000045). A total of 40.7% of patients in Group Chronic Pain, and 21.9% in Group Non-Chronic Pain demonstrated poorer sleep quality according to the Pittsburgh Sleep Quality Index scores, with a cut-off level > 5. A moderate positive correlation was found between the global Pittsburgh Sleep Quality Index and Visual Analog Scale scores (r = 0.310, p < 0.01). A multiple linear regression analysis showed that age, gender, income, Visual Analog Scale, and presence of depression were the significant predictors for Pittsburgh Sleep Quality Index score. CONCLUSIONS The current study revealed that chronic pain and pain intensity are important predictors of sleep quality.
Collapse
|
13
|
Inclusive search for supersymmetry using razor variables in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2013; 111:081802. [PMID: 24010428 DOI: 10.1103/physrevlett.111.081802] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Indexed: 06/02/2023]
Abstract
An inclusive search is presented for new heavy particle pairs produced in √s=7 TeV proton-proton collisions at the LHC using 4.7±0.1 fb(-1) of integrated luminosity. The selected events are analyzed in the 2D razor space of M(R), an event-by-event indicator of the heavy particle mass scale, and R, a dimensionless variable related to the missing transverse energy. The third-generation sector is probed using the event heavy-flavor content. The search is sensitive to generic supersymmetry models with minimal assumptions about the superpartner decay chains. No excess is observed in the number of events beyond that predicted by the standard model. Exclusion limits are derived in the CMSSM framework as well as for simplified models. Within the CMSSM parameter space considered, gluino masses up to 800 GeV and squark masses up to 1.35 TeV are excluded at 95% confidence level depending on the model parameters. The direct production of pairs of top or bottom squarks is excluded for masses as high as 400 GeV.
Collapse
|
14
|
Search for physics beyond the standard model in events with τ leptons, jets, and large transverse momentum imbalance in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2493. [PMID: 25814865 PMCID: PMC4370880 DOI: 10.1140/epjc/s10052-013-2493-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 06/11/2013] [Indexed: 06/04/2023]
Abstract
A search for physics beyond the standard model is performed with events having one or more hadronically decaying τ leptons, highly energetic jets, and large transverse momentum imbalance. The data sample corresponds to an integrated luminosity of 4.98 fb-1 of proton-proton collisions at [Formula: see text] collected with the CMS detector at the LHC in 2011. The number of observed events is consistent with predictions for standard model processes. Lower limits on the mass of the gluino in supersymmetric models are determined.
Collapse
|
15
|
Effects of isoflurane in an intoxication model: experimental study. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2013; 17:1738-1743. [PMID: 23852896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BACKGROUND Isoflurane is a volatile anaesthetic that has been commonly used since 1980. The major metabolites of isoflurane are fluoride ion and trifluoroacetate, both excreted in the urine. AIM This study manage to show the histopathological findings of ingested isoflurane on liver, kidney and lugs in an animal model. Twenty-one rabbits were selected and divided into three groups: Group Isoflurane-5 (I-5); Group Isoflurane-10 (I-10); and Group Control (C). Each group consisted of seven rabbits. I-5 and I-10 received 5 ml/kg and 10 ml/kg of liquid isoflurane, respectively, via nasogastric tube, while C received 5 ml/kg saline (0.9% NaCI). All animals in I-5 and I-10 were sacrificed without anesthetic drug administration. Tissue samples from livers, kidneys and lungs were collected, preserving tissue unity and avoiding infliction of any trauma. Samples were fixed in 10% formalin solution, embedded in paraffin blocks and sliced into 5 μm sections. To investigate the effects of isoflurane, sections were examined under light microscope and histopathological changes were scored. RESULTS Mean injury scores and the appearance of portal lymphocyte infiltration in liver samples showed significant increases in I-5 and I-10 compared to C (p = 0.005, p = 0.001 and p = 0.001, respectively). Mean lung injury scores revealed significant increases after isoflurane treatment in I-5 and I-10 compared to C (p = 0.026 and p = 0.017, respectively). CONCLUSIONS Ingested isoflurane led to mild liver and lung injuries in rabbits.
Collapse
|
16
|
Search for supersymmetry in pp collisions at [Formula: see text] TeV in events with a single lepton, jets, and missing transverse momentum. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2404. [PMID: 25814857 PMCID: PMC4370766 DOI: 10.1140/epjc/s10052-013-2404-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 03/02/2013] [Indexed: 05/30/2023]
Abstract
Results are reported from a search for new physics processes in events containing a single isolated high-transverse-momentum lepton (electron or muon), energetic jets, and large missing transverse momentum. The analysis is based on a 4.98 fb-1 sample of proton-proton collisions at a center-of-mass energy of 7 TeV, obtained with the CMS detector at the LHC. Three separate background estimation methods, each relying primarily on control samples in the data, are applied to a range of signal regions, providing complementary approaches for estimating the background yields. The observed yields are consistent with the predicted standard model backgrounds. The results are interpreted in terms of limits on the parameter space for the constrained minimal supersymmetric extension of the standard model, as well as on cross sections for simplified models, which provide a generic description of the production and decay of new particles in specific, topology based final states. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (doi:10.1140/epjc/s10052-013-2404-z) contains supplementary material, which is available to authorized users.
Collapse
|
17
|
Measurement of associated production of vector bosons and top quark-antiquark pairs in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:172002. [PMID: 23679709 DOI: 10.1103/physrevlett.110.172002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Indexed: 06/02/2023]
Abstract
The first measurement of vector-boson production associated with a top quark-antiquark pair in proton-proton collisions at sqrt[s] = 7 TeV is presented. The results are based on a data set corresponding to an integrated luminosity of 5.0 fb(-1), recorded by the CMS detector at the LHC in 2011. The measurement is performed in two independent channels through a trilepton analysis of ttZ events and a same-sign dilepton analysis of ttV (V = W or Z) events. In the trilepton channel a direct measurement of the ttZ cross section σ(ttZ) = 0.28(-0.11)(+0.14) (stat)(-0.03)(+0.06) (syst) pb is obtained. In the dilepton channel a measurement of the ttV cross section yields σ(ttV) = 0.43(-0.15)(+0.17) (stat)(-0.07)(+0.09) (syst) pb. These measurements have a significance, respectively, of 3.3 and 3.0 standard deviations from the background hypotheses and are compatible, within uncertainties, with the corresponding next-to-leading order predictions of 0.137(-0.016)(+0.012) and 0.306(-0.053)(+0.031) pb.
Collapse
|
18
|
Search for new physics in final states with a lepton and missing transverse energy inppcollisions at the LHC. Int J Clin Exp Med 2013. [DOI: 10.1103/physrevd.87.072005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
19
|
Search for pair-produced dijet resonances in four-jet final states in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:141802. [PMID: 25166980 DOI: 10.1103/physrevlett.110.141802] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Indexed: 06/03/2023]
Abstract
A search for the pair production of a heavy, narrow resonance decaying into two jets has been performed using events collected in sqrt[s] = 7 TeV pp collisions with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 5.0 fb(-1). Events are selected with at least four jets and two dijet combinations with similar dijet mass. No resonances are found in the dijet mass spectrum. The upper limit at 95% confidence level on the product of the resonance pair production cross section, the branching fractions into dijets, and the acceptance varies from 0.22 to 0.005 pb, for resonance masses between 250 and 1200 GeV. Pair-produced colorons decaying into qq are excluded for coloron masses between 250 and 740 GeV.
Collapse
|
20
|
Search for contact interactions using the inclusive jetpTspectrum inppcollisions ats=7 TeV. Int J Clin Exp Med 2013. [DOI: 10.1103/physrevd.87.052017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
21
|
Search for pair production of third-generation leptoquarks and top squarks in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:081801. [PMID: 23473129 DOI: 10.1103/physrevlett.110.081801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Indexed: 06/01/2023]
Abstract
Results are presented from a search for the pair production of third-generation scalar and vector leptoquarks, as well as for top squarks in R-parity-violating supersymmetric models. In either scenario, the new, heavy particle decays into a τ lepton and a b quark. The search is based on a data sample of pp collisions at sqrt[s] = 7 TeV, which is collected by the CMS detector at the LHC and corresponds to an integrated luminosity of 4.8 fb(-1). The number of observed events is found to be in agreement with the standard model prediction, and exclusion limits on mass parameters are obtained at the 95% confidence level. Vector leptoquarks with masses below 760 GeV are excluded and, if the branching fraction of the scalar leptoquark decay to a τ lepton and a b quark is assumed to be unity, third-generation scalar leptoquarks with masses below 525 GeV are ruled out. Top squarks with masses below 453 GeV are excluded for a typical benchmark scenario, and limits on the coupling between the top squark, τ lepton, and b quark, λ(333)(') are obtained. These results are the most stringent for these scenarios to date.
Collapse
|
22
|
Measurement of the Υ1S, Υ2S, and Υ3S polarizations in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:081802. [PMID: 23473130 DOI: 10.1103/physrevlett.110.081802] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Indexed: 06/01/2023]
Abstract
The polarizations of the Υ(1S), Υ(2S), and Υ(3S) mesons are measured in proton-proton collisions at sqrt[s] = 7 TeV, using a data sample of Υ(nS) → μ +μ- decays collected by the CMS experiment, corresponding to an integrated luminosity of 4.9 fb(-1). The dimuon decay angular distributions are analyzed in three different polarization frames. The polarization parameters λ[symbol see text], λ(φ), and λ([symbol see text]φ), as well as the frame-invariant quantity λ, are presented as a function of the Υ(nS) transverse momentum between 10 and 50 GeV, in the rapidity ranges |y|<0.6 and 0.6<|y|<1.2. No evidence of large transverse or longitudinal polarizations is seen in the explored kinematic region.
Collapse
|
23
|
Study of the mass and spin-parity of the Higgs boson candidate via its decays to Z boson pairs. PHYSICAL REVIEW LETTERS 2013; 110:081803. [PMID: 23473131 DOI: 10.1103/physrevlett.110.081803] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Indexed: 06/01/2023]
Abstract
A study is presented of the mass and spin-parity of the new boson recently observed at the LHC at a mass near 125 GeV. An integrated luminosity of 17.3 fb(-1), collected by the CMS experiment in proton-proton collisions at center-of-mass energies of 7 and 8 TeV, is used. The measured mass in the ZZ channel, where both Z bosons decay to e or μ pairs, is 126.2 ± 0.6(stat) ± 0.2(syst) GeV. The angular distributions of the lepton pairs in this channel are sensitive to the spin-parity of the boson. Under the assumption of spin 0, the present data are consistent with the pure scalar hypothesis, while disfavoring the pure pseudoscalar hypothesis.
Collapse
|
24
|
Measurement of the sum of WW and WZ production with W+dijet events in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2283. [PMID: 25814853 PMCID: PMC4370803 DOI: 10.1140/epjc/s10052-013-2283-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 12/20/2012] [Indexed: 06/02/2023]
Abstract
A measurement of the inclusive WW+WZ diboson production cross section in proton-proton collisions is reported, based on events containing a leptonically decaying W boson and exactly two jets. The data sample, collected at [Formula: see text] with the CMS detector at the LHC, corresponds to an integrated luminosity of 5.0 fb-1. The measured value of the sum of the inclusive WW and WZ cross sections is σ(pp→WW+WZ)=68.9±8.7 (stat.)±9.7 (syst.)±1.5 (lum.) pb, consistent with the standard model prediction of 65.6±2.2 pb. This is the first measurement of WW+WZ production in pp collisions using this signature. No evidence for anomalous triple gauge couplings is found and upper limits are set on their magnitudes.
Collapse
|
25
|
|
26
|
Measurement of the azimuthal anisotropy of neutral pions in Pb-Pb collisions at sqrt[s](NN)] = 2.76 TeV. PHYSICAL REVIEW LETTERS 2013; 110:042301. [PMID: 25166155 DOI: 10.1103/physrevlett.110.042301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2012] [Indexed: 06/03/2023]
Abstract
First measurements of the azimuthal anisotropy of neutral pions produced in Pb-Pb collisions at a center-of-mass energy of sqrt[s(NN)] = 2.76 TeV are presented. The amplitudes of the second Fourier component (v(2)) of the π(0) azimuthal distributions are extracted using an event-plane technique. The values of v(2) are studied as a function of the neutral pion transverse momentum (p(T)) for different classes of collision centrality in the kinematic range 1.6<p(T) <8.0 GeV/c, within the pseudorapidity interval |η|<0.8. The CMS measurements of v(2) (p(T)) are similar to previously reported π(0) azimuthal anisotropy results from sqrt[s(NN)] = 200 GeV Au-Au collisions at RHIC, despite a factor of ∼ 14 increase in the center-of-mass energy. In the momentum range 2.5<p(T)<5.0 GeV/c, the neutral pion anisotropies are found to be smaller than those observed by CMS for inclusive charged particles.
Collapse
|
27
|
Evidence for associated production of a single top quark and W boson in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:022003. [PMID: 23383893 DOI: 10.1103/physrevlett.110.022003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Indexed: 06/01/2023]
Abstract
Evidence is presented for the associated production of a single top quark and W boson in pp collisions at sqrt[s]=7 TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 4.9 fb(-1). The measurement is performed using events with two leptons and a jet originated from a b quark. A multivariate analysis based on kinematic properties is utilized to separate the tt background from the signal. The observed signal has a significance of 4.0σ and corresponds to a cross section of 16(-4)(+5) pb, in agreement with the standard model expectation of 15.6±0.4(-1.2)(+1.0) pb.
Collapse
|
28
|
Search for heavy neutrinos and W(R) bosons with right-handed couplings in a left-right symmetric model in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:261802. [PMID: 23368549 DOI: 10.1103/physrevlett.109.261802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Indexed: 06/01/2023]
Abstract
Results are presented from a search for heavy, right-handed muon neutrinos, N(μ), and right-handed W(R) bosons, which arise in the left-right symmetric extensions of the standard model. The analysis is based on a 5.0 fb(-1) sample of proton-proton collisions at a center-of-mass energy of 7 TeV, collected by the CMS detector at the Large Hadron Collider. No evidence is observed for an excess of events over the standard model expectation. For models with exact left-right symmetry, heavy right-handed neutrinos are excluded at 95% confidence level for a range of neutrino masses below the W(R) mass, dependent on the value of M(W(R)). The excluded region in the two-dimensional (M(W(R)), M(N(μ)) mass plane extends to M(W(R))=2.5 TeV.
Collapse
|
29
|
Study of the Dijet mass spectrum in pp → W+jets events at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:251801. [PMID: 23368450 DOI: 10.1103/physrevlett.109.251801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Indexed: 06/01/2023]
Abstract
We report an investigation of the invariant mass spectrum of the two jets with highest transverse momentum in pp → W+2-jet and W+3-jet events to look for resonant enhancement. The data sample corresponds to an integrated luminosity of 5.0 fb(-1) collected with the CMS detector at sqrt[s] = 7 TeV. We find no evidence for the anomalous structure reported by the CDF Collaboration, and establish an upper limit of 5.0 pb at 95% confidence level on the production cross section for a generic Gaussian signal with mass near 150 GeV. Additionally, we exclude two theoretical models that predict a CDF-like dijet resonance near 150 GeV.
Collapse
|
30
|
Measurement of the relative prompt production rate of χc2 and χc1 in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2012; 72:2251. [PMID: 25814834 PMCID: PMC4370953 DOI: 10.1140/epjc/s10052-012-2251-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 11/17/2012] [Indexed: 05/28/2023]
Abstract
A measurement is presented of the relative prompt production rate of χc2 and χc1 with 4.6 fb-1 of data collected by the CMS experiment at the LHC in pp collisions at [Formula: see text]. The two states are measured via their radiative decays χc→J/ψ+γ, with the photon converting into an e+e- pair for J/ψ rapidity |y(J/ψ)|<1.0 and photon transverse momentum pT(γ)>0.5 GeV/c. The measurement is given for six intervals of pT(J/ψ) between 7 and 25 GeV/c. The results are compared to theoretical predictions.
Collapse
|
31
|
Observation of sequential Υ suppression in PbPb collisions. PHYSICAL REVIEW LETTERS 2012; 109:222301. [PMID: 23368113 DOI: 10.1103/physrevlett.109.222301] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Indexed: 06/01/2023]
Abstract
The suppression of the individual Υ(nS) states in PbPb collisions with respect to their yields in pp data has been measured. The PbPb and pp data sets used in the analysis correspond to integrated luminosities of 150 μb(-1) and 230 nb(-1), respectively, collected in 2011 by the CMS experiment at the LHC, at a center-of-mass energy per nucleon pair of 2.76 TeV. The Υ(nS) yields are measured from the dimuon invariant mass spectra. The suppression of the Υ(nS) yields in PbPb relative to the yields in pp, scaled by the number of nucleon-nucleon collisions, R(AA), is measured as a function of the collision centrality. Integrated over centrality, the R(AA) values are 0.56±0.08(stat)±0.07(syst), 0.12±0.04(stat)±0.02(syst), and lower than 0.10 (at 95% confidence level), for the Υ(1S), Υ(2S), and Υ(3S) states, respectively. The results demonstrate the sequential suppression of the Υ(nS) states in PbPb collisions at LHC energies.
Collapse
|
32
|
Search for a W' or techni-ρ decaying into WZ in pp Collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:141801. [PMID: 23083236 DOI: 10.1103/physrevlett.109.141801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Indexed: 06/01/2023]
Abstract
A search is performed in pp collisions at sqrt[s]=7 TeV for exotic particles decaying via WZ to final states with electrons and muons. The data sample corresponds to an integrated luminosity of approximately 5 fb(-1). No significant excess is observed in the data above the expected standard model background. Upper bounds at 95% confidence level are set on the production cross section of the W' boson described by the sequential standard model and on the W' WZ coupling. W' bosons with masses below 1143 GeV are excluded. Limits are also set in the context of low-scale technicolor models, under a range of assumptions concerning the model parameters.
Collapse
|
33
|
Measurement of the B0 production cross section in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:252001. [PMID: 21770632 DOI: 10.1103/physrevlett.106.252001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Indexed: 05/31/2023]
Abstract
Measurements of the differential production cross sections dσ/dpTB and dσ/dyB for B0 mesons produced in pp collisions at sqrt[s] = 7 TeV are presented. The data set used was collected by the CMS experiment at the LHC and corresponds to an integrated luminosity of 40 pb-1. The production cross section is measured from B0 meson decays reconstructed in the exclusive final state J/ψKS0, with the subsequent decays J/ψ → μ + μ - and KS0 → π+}π-. The total cross section for pTB>5 GeV and |yB|<2.2 is measured to be 33.2 ± 2.5 ± 3.5 μb, where the first uncertainty is statistical and the second is systematic.
Collapse
|
34
|
Search for neutral minimal supersymmetric standard model Higgs bosons decaying to tau pairs in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:231801. [PMID: 21770497 DOI: 10.1103/physrevlett.106.231801] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Indexed: 05/31/2023]
Abstract
A search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36 pb(-1) recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fraction to tau pairs, as a function of the pseudoscalar Higgs boson mass, yield stringent new bounds in the MSSM parameter space.
Collapse
|
35
|
Search for supersymmetry in pp collisions at √7 TeV in events with two photons and missing transverse energy. PHYSICAL REVIEW LETTERS 2011; 106:211802. [PMID: 21699288 DOI: 10.1103/physrevlett.106.211802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Indexed: 05/31/2023]
Abstract
A search for supersymmetry in the context of general gauge-mediated breaking with the lightest neutralino as the next-to-lightest supersymmetric particle and the gravitino as the lightest is presented. The data sample corresponds to an integrated luminosity of 36 pb(-1) recorded by the CMS experiment at the LHC. The search is performed by using events containing two or more isolated photons, at least one hadronic jet, and significant missing transverse energy. No excess of events at high missing transverse energy is observed. Upper limits on the signal cross section for general gauge-mediated supersymmetry between 0.3 and 1.1 pb at the 95% confidence level are determined for a range of squark, gluino, and neutralino masses, excluding supersymmetry parameter space that was inaccessible to previous experiments.
Collapse
|
36
|
Study of Z Boson Production in PbPb Collisions at √S(NN)=2.76 TeV. PHYSICAL REVIEW LETTERS 2011; 106:212301. [PMID: 21699291 DOI: 10.1103/physrevlett.106.212301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Indexed: 05/31/2023]
Abstract
A search for Z bosons in the μ(+)μ(-) decay channel has been performed in PbPb collisions at √S(NN)=2.76 TeV with the CMS detector at the LHC, in a 7.2 μb(-1) data sample. The number of opposite-sign muon pairs observed in the 60-120 GeV/c(2) invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of [33.8±5.5(stat)±4.4(syst)]×10(-8), in the |y|<2.0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.
Collapse
|
37
|
Measurement of dijet angular distributions and search for quark compositeness in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:201804. [PMID: 21668222 DOI: 10.1103/physrevlett.106.201804] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Indexed: 05/30/2023]
Abstract
Dijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at √s = 7 TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36 pb⁻¹. The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction scale for left-handed quarks of Λ⁺ = 5.6 TeV (Λ⁻ = 6.7 TeV) for destructive (constructive) interference is obtained at the 95% confidence level.
Collapse
|
38
|
Search for pair production of second-generation scalar leptoquarks in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:201803. [PMID: 21668221 DOI: 10.1103/physrevlett.106.201803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Indexed: 05/30/2023]
Abstract
A search for pair production of second-generation scalar leptoquarks in the final state with two muons and two jets is performed using proton-proton collision data at √s = 7 TeV collected by the CMS detector at the LHC. The data sample used corresponds to an integrated luminosity of 34 pb⁻¹. The number of observed events is in good agreement with the predictions from the standard model processes. An upper limit is set on the second-generation leptoquark cross section times β² as a function of the leptoquark mass, and leptoquarks with masses below 394 GeV are excluded at a 95% confidence level for β = 1, where β is the leptoquark branching fraction into a muon and a quark. These limits are the most stringent to date.
Collapse
|
39
|
Search for pair production of first-generation scalar leptoquarks in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:201802. [PMID: 21668220 DOI: 10.1103/physrevlett.106.201802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Indexed: 05/30/2023]
Abstract
A search for pair production of first-generation scalar leptoquarks is performed in the final state containing two electrons and two jets using proton-proton collision data at √s = 7 TeV. The data sample used corresponds to an integrated luminosity of 33 pb⁻¹ collected with the CMS detector at the CERN LHC. The number of observed events is in good agreement with the predictions for the standard model background processes, and an upper limit is set on the leptoquark pair production cross section times β² as a function of the leptoquark mass, where β is the branching fraction of the leptoquark decay to an electron and a quark. A 95% confidence level lower limit is set on the mass of a first-generation scalar leptoquark at 384 GeV for β = 1, which is the most stringent direct limit to date.
Collapse
|
40
|
Dijet azimuthal decorrelations in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:122003. [PMID: 21517306 DOI: 10.1103/physrevlett.106.122003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Indexed: 05/30/2023]
Abstract
Measurements of dijet azimuthal decorrelations in pp collisions at √s=7 TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding to an integrated luminosity of 2.9 pb⁻¹. The results are compared to predictions from perturbative QCD calculations and various Monte Carlo event generators. The dijet azimuthal distributions are found to be sensitive to initial-state gluon radiation.
Collapse
|
41
|
Measurement of the B(+) production cross section in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:112001. [PMID: 21469857 DOI: 10.1103/physrevlett.106.112001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Indexed: 05/30/2023]
Abstract
Measurements of the total and differential cross sections dσ/dp(T)(B) and dσ/dy(B) for B(+) mesons produced in pp collisions at sqrt[s]=7 TeV are presented. The data correspond to an integrated luminosity of 5.8 pb(-1) collected by the CMS experiment operating at the LHC. The exclusive decay B(+)→J/ψK(+), with J/ψ→μ(+)μ(-), is used to detect B(+) mesons and to measure the production cross section as a function of p(T)(B) and y(B). The total cross section for p(T)(B)>5 GeV and |y(B)|<2.4 is measured to be 28.1±2.4±2.0±3.1 μb, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement.
Collapse
|
42
|
Measurement of the isolated prompt photon production cross section in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:082001. [PMID: 21405566 DOI: 10.1103/physrevlett.106.082001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 01/15/2011] [Indexed: 05/30/2023]
Abstract
The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E(T)(γ) in pp collisions at √s=7 TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.9 pb(-1). Photons are required to have a pseudorapidity |η(γ)|<1.45 and E(T)(γ)>21 GeV, covering the kinematic region 0.006<x(T)<0.086. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations.
Collapse
|
43
|
Search for stopped Gluinos in pp collisions at square root s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:011801. [PMID: 21231732 DOI: 10.1103/physrevlett.106.011801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Indexed: 05/30/2023]
Abstract
The results of the first search for long-lived gluinos produced in 7 TeV pp collisions at the CERN Large Hadron Collider are presented. The search looks for evidence of long-lived particles that stop in the CMS detector and decay in the quiescent periods between beam crossings. In a dataset with a peak instantaneous luminosity of 1×10(32) cm-2 s-1, an integrated luminosity of 10 pb-1, and a search interval corresponding to 62 hours of LHC operation, no significant excess above background was observed. Limits at the 95% confidence level on gluino pair production over 13 orders of magnitude of gluino lifetime are set. For a mass difference mg - mχ1(0) >100 GeV/c2, and assuming BR(g→gχ1(0))=100%, mg < 370 GeV/c2 are excluded for lifetimes from 10 μs to 1000 s.
Collapse
|
44
|
Search for quark compositeness with the dijet centrality ratio in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2010; 105:262001. [PMID: 21231646 DOI: 10.1103/physrevlett.105.262001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Indexed: 05/30/2023]
Abstract
A search for quark compositeness in the form of quark contact interactions, based on hadronic jet pairs (dijets) produced in proton-proton collisions at √s=7 TeV, is described. The data sample of the study corresponds to an integrated luminosity of 2.9 pb(-1) collected with the CMS detector at the LHC. The dijet centrality ratio, which quantifies the angular distribution of the dijets, is measured as a function of the invariant mass of the dijet system and is found to agree with the predictions of the standard model. A statistical analysis of the data provides a lower limit on the energy scale of quark contact interactions. The sensitivity of the analysis is such that the expected limit is 2.9 TeV; because the observed value of the centrality ratio at high invariant mass is below the expectation, the observed limit is 4.0 TeV at the 95% confidence level.
Collapse
|
45
|
Search for dijet resonances in 7 TeV pp collisions at CMS. PHYSICAL REVIEW LETTERS 2010; 105:211801. [PMID: 21231289 DOI: 10.1103/physrevlett.105.211801] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Indexed: 05/30/2023]
Abstract
A search for narrow resonances in the dijet mass spectrum is performed using data corresponding to an integrated luminosity of 2.9 pb⁻¹ collected by the CMS experiment at the Large Hadron Collider. Upper limits at the 95% confidence level are presented on the product of the resonance cross section, branching fraction into dijets, and acceptance, separately for decays into quark-quark, quark-gluon, or gluon-gluon pairs. The data exclude new particles predicted in the following models at the 95% confidence level: string resonances, with mass less than 2.50 TeV, excited quarks, with mass less than 1.58 TeV, and axigluons, colorons, and E6 diquarks, in specific mass intervals. This extends previously published limits on these models.
Collapse
|
46
|
First measurement of Bose-Einstein correlations in proton-proton collisions at √s=0.9 and 2.36 TeV at the LHC. PHYSICAL REVIEW LETTERS 2010; 105:032001. [PMID: 20867758 DOI: 10.1103/physrevlett.105.032001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Indexed: 05/29/2023]
Abstract
Bose-Einstein correlations have been measured using samples of proton-proton collisions at 0.9 and 2.36 TeV center-of-mass energies, recorded by the CMS experiment at the CERN Large Hadron Collider. The signal is observed in the form of an enhancement of pairs of same-sign charged particles with small relative four-momentum. The size of the correlated particle emission region is seen to increase significantly with the particle multiplicity of the event.
Collapse
|
47
|
Transverse-momentum and pseudorapidity distributions of charged hadrons in pp collisions at square root of s = 7 TeV. PHYSICAL REVIEW LETTERS 2010; 105:022002. [PMID: 20867699 DOI: 10.1103/physrevlett.105.022002] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Indexed: 05/29/2023]
Abstract
Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at square root of s = 7 TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit pairs, and fully reconstructed charged-particle tracks. The combination of the three methods gives a charged-particle multiplicity per unit of pseudorapidity dN(ch)/dη|(|η|<0.5) = 5.78 ± 0.01(stat) ± 0.23(syst) for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from square root of s = 0.9 to 7 TeV is [66.1 ± 1.0(stat) ± 4.2(syst)]%. The mean transverse momentum is measured to be 0.545 ± 0.005(stat) ± 0.015(syst) GeV/c. The results are compared with similar measurements at lower energies.
Collapse
|
48
|
Abstract
Sexual dysfunction (SD) is common among end-stage renal disease (ESRD patients). Studies about SD in the posttransplantation period have reported various results. The aim of this study was to investigate SD prevalence and relationship to sociodemographic and clinical variables. Sexual functioning was measured using the Arizona Sexual Experiences Scale (ASEX), and depression by the Beck Depression Inventory (BDI) in 98 patients. We observed that 68 patients (69.4%) had SD; the prevalence rates were 56.9% for men and 93.4% for women. ASEX item scores among single patients were higher than those among married patients. Subjects with SD were more depressed (P < .001) and less educated (for female patients, P = .02). These findings showed that SD is common in Turkish patients, especially women. SD patients should be integrated into routine examination throughout the transplant, process, and when needed, their treatment management should include education regarding sexual life complaints.
Collapse
|
49
|
Abstract
INTRODUCTION Sleep and sleep-related disorders are common among end-stage renal disease patients. In the general population and hemodialysis patients, insomnia impairs health-related quality of life (HRQOL). The aims of this study were to examine the prevalence of sleep problems among renal transplantation patients and the relationship between the quality of sleep and the HRQOL. METHODS Pittsburgh Sleep Quality Index (PSQI) for measuring quality of sleep, WHOQOL-BREF for quality of life, and Beck Depression Inventory (BDI) were applied to 100 renal transplant patients. RESULTS Thirty (30%) subjects were "poor sleepers" (global PSQI > 5). Poor sleepers were younger (mean age: 31 vs 37); less educated (mean years of education: 7.80 vs 9.55), and more depressed (mean BDI scores 13.63 vs 7.18). There were significant inverse correlations between global PSQI and physical health (r = -0.31; P < .001) and psychological state (r = -.20; P = .04) with a significant correlation with BDI scores (r = .36; P < .001). The BDI score (P < .001) was the only significant factor of physical health, psychological state, and social functioning. BDI score (P < .001) and education (P < .022) were significant predictors of environmental conditions. CONCLUSION Sleep problems are not as common among transplant as dialysis patients, but still higher than the general population. Poor sleep seems to be a part of depressive symptomatology. Severity of depression and lower education were more negatively effective factors on the quality of life of these patients than the quality of sleep.
Collapse
|
50
|
Anxiety, depression and stressful life events among medical students: a prospective study in Antalya, Turkey. MEDICAL EDUCATION 2001; 35:12-7. [PMID: 11123589 DOI: 10.1046/j.1365-2923.2001.00726.x] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
OBJECTIVE To assess psychological changes in medical students in Antalya, Turkey during their undergraduate education. The first-year follow-up outcomes are presented in this article. DESIGN All first-year undergraduate students were given a detailed, self-report questionnaire and another in the second year. They were asked to complete the General Health Questionnaire (GHQ), the Spielberger State-Trait Anxiety Inventory (STAI) and the Beck Depression Inventory (BDI). SETTING The Faculties of Medicine, Economics and Physical Education (PE) of the Akdeniz University, Antalya, Turkey. PARTICIPANTS All first-year undergraduate students in the Faculties of Medicine, Economics and PE who were registered in 1996. RESULTS The findings showed that psychological test scores on the GHQ, the STAI and the BDI rose significantly in medical students between the first and second years. Using the GHQ, with different cut-off scores, the percentage of students scoring above the thresholds was higher in medical students in year 2, compared with economics and PE students. In addition, the scores for some stressful life events of medical students showed a significant rise from year 1 to year 2. Multiple regression analyses indicated that some stressful life events related to social activities were associated with the psychological test scores for medical students. CONCLUSION The results indicate that there is a decrease in the psychological health of first-year medical students. Some inadequacies in the social activities of the students might play a role in this type of disturbance.
Collapse
|