Bladder training compared to bladder training associated with pelvic floor muscle training for overactive bladder symptoms in women: A randomized clinical trial

AIMS

To compare the effects of bladder training (BT) versus BT with pelvic floor muscle training (PFMT) in women with overactive bladder (OAB) symptoms.

METHODS

Randomized controlled clinical trial including women with OAB symptoms, randomized into two groups: BT versus BT + PFMT. For 12 consecutive weeks, the women received home BT. The BT + PFMT performed supervised PFMT, once/week, associated at home PFMT protocol. Primary outcomes were urinary urgency, daytime voiding frequency, nocturia and urgency urinary incontinence assisted by both 3-day bladder diary and International Consultation on Incontinence OAB (ICIQ-OAB) questionnaire. Secondary outcomes were 24-h pad test and Patient Global Impression of Improvement. T-test, analysis of variance, Mann-Whitney (SPSS 20.0) and power/effect size (G-power) were applied in data analyses.

RESULTS

Sixty-three women were included (B = 31; BT + PFMT = 32). There was no significant statistical difference between groups in terms of urinary symptoms: daytime frequency (BT: pre: 11.59 [±5.80], post: 9.10 [±4.05]; BT + PFMT: pre: 10.67 [±3.73], post: 8.08 [±3.38]) p = 0.75; nocturia: (BT: pre: 1.46 [±0.91], post: 0.82 [±0.82]; BT + PFMT: pre: 1.80 [±2.26], post: 0.82 [±1.15]) p = 0.70; urinary urgency (BT: pre: 3.22 [±4.70], post: 4.49 [±4.32]; BT + PFMT: pre: 6.87 [±5.60], post: 6.15 [±4.52]) p = 0.10; ICIQ-OAB total score: (BT: pre: 9.16 [±2.55], post: 6.32 [±3.77]; (BT + PFMT: pre: 9.75 [±2.06], post: 5.06 [±3.44] p = 0.30.

CONCLUSIONS

Supervised PFMT added to BT did not provide further improvements than isolated BT in women with OAB symptoms.

Interaction between the impact of the Coronavirus disease 2019 pandemic and demographic characteristics on sexual/erectile dysfunction in Latin America: cross-sectional study

Aim:

Our objective was to investigate whether there is an interaction between the COVID-19 pandemic, demographic characteristics and erectile/sexual (E/S) function in individuals from Latin America.

Materials and Methods:

Cross-sectional study which included Latin American individuals over 18 years old, recruited through social media and interviewed between July and August 2020 by online surveys (Google Forms) in Portuguese and Spanish languages. The E/S function was evaluated through the following questionnaires: Simplified International Index of Erectile Function (IIEF-5) and Female Sexual Function Index (FSFI); while post-traumatic stress disorder (PTSD) triggered by the COVID-19 pandemic was assessed through the Impact of Event Scale Revised (IES-R). The data was analyzed by T Student, bivariate and multivariate logistic regression, with significance determined by the Wald test (p<0.05), using the R software v4.0.

Results:

Out of the 2016 individuals that responded to the survey, 1986 were included and 743 of them presented E/S dysfunction. PTSD occurrence was greater among people with E/S dysfunction when compared to those without E/S dysfunction, in the total score (males: IES-R=26.54[±19.17] and females: IES-R=35.92[±19.25]) and also in the three domains. It was found that those who do not live with a partner were 74% more likely to have E/S dysfunction, but living with a partner during the pandemic had a greater impact on E/S function.

Conclusion:

A negative interaction between the impact of the COVID-19 pandemic and erectile/sexual function of the Latin American population was observed, with greater implications among the individuals who live with their partners.

Electromyographic analysis of maximal voluntary contraction of female pelvic floor muscles: Intrarater and interrater reliability study

AIMS

To investigate the intrarater and interrater reliability of the surface electromyography (sEMG) of female pelvic floor muscles (PFM) by visual determination of the onset-offset during maximal voluntary contraction (MVC).

METHODS

Intrarater and interrater reliability study. Three MVC, recorded for 5 s (s) each and separated by intervals of 60 s, were requested. Two independent raters visually determined the onset and offset of each MVC. The agreement between raters on the quality of the signals was analyzed both qualitatively (visual inspection) and quantitatively (signal-to-noise ratio, SNR). The reliability of integral and median frequency (MDF) of sEMG signals during MVC was analyzed using intraclass correlation coefficient (ICC) models (ICC_2,1 , ICC_2,3 ) and repeated measures analysis of variance.

RESULTS

A total of 58 women (mean age of 54 years) and two independent raters participated in the analyses. Of the total, 22 (37.9%) were considered of high quality by both raters and the SNR ranged 34.3-22.2 decibels (dB). The agreement of qualitative visual evaluation of the sEMG signal was fair (Cohen's κ = 0.306 [0.148; 0.463]). Intrarater and interrater reliability were excellent for the average of the three MVC, both for integral (ICC_2,3  = 0.884 [0.821; 0.925]; ω²  = -0.006, p = 0.558) and MDF (ICC_2,3  = 0.998 [0.998; 0.999]; ω²  = -0.009, p = 0.992).

CONCLUSION

Qualitative visual analysis of the sEMG signal presents fair interrater agreement and reflects the SNR. Visual determination of the onset and offset of the MVC of PFM using the standard interface of the sEMG software has excellent reliability for determination of muscle activation variables.

Can Supervised Pelvic Floor Muscle Training Through Gametherapy Relieve Urinary Incontinence Symptoms in Climacteric Women? A Feasibility Study

OBJECTIVE

 To investigate the feasibility of pelvic floor muscle training (PFMT) through gametherapy for relieving urinary symptoms of climacteric women with stress or mixed urinary incontinence (UI).

METHODS

 Randomized clinical trial, divided into two groups: Gametherapy (G_Game) and Control (G_Control). Both groups received recommendations about unsupervised PFMT, and G_Game also received supervised PFMT through gametherapy. After 5 consecutive weeks, the feasibility was investigated considering participant adherence, urinary symptoms (evaluated by the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form [ICIQ-UI-SF] questionnaire), and pelvic floor function (PERFECT Scheme: power, endurance, repetition and fast). The Fisher exact, Kruskal-Wallis, Wilcoxon sign paired, and Mann-Whitney U tests were used by intention-to-treat analysis, using STATA 15.1 (StataCorp, College Station, TX, USA) software.

RESULTS

 The present study included 20 women per group and observed a higher adherence in G_Game. In the intragroup analysis, a decrease in the ICIQ-UI-SF score was observed in both groups (14.0 to 10.0; 13.5 to 0), associated with increased endurance (2.5 to 3.5; 2.5 to 4.0) in G_Control and G_Game, respectively. Moreover, there was a concomitant increase in pelvic floor muscles (PFMs) power (2.0 to 3.0), repetition (3.0 to 5.0), and fast (10.0 to 10.0) in G_Game. In the intergroup analysis, a reduction of UI was observed (p < 0.001; r = 0.8), as well an increase in PFM power (p = 0.027, r = 0.2) and endurance (p = 0.033; r = 0.3) in G_Game.

CONCLUSION

 The feasibility of supervised PFMT through gametherapy was identified by observing participant adherence, relief of urinary symptoms, and improvement in PFM function.

The Brazilian version of the Health-Related Quality of Life Questionnaire for Nausea and Vomiting of Pregnancy: translation, cross-cultural adaptation and reliability - an observational cross-sectional study

BACKGROUND

The Health-Related Quality of Life Questionnaire for Nausea and Vomiting of Pregnancy (NVPQOL) is a validated questionnaire assessing quality of life among pregnant women with nausea and vomiting.

OBJECTIVE

To translate, cross-culturally adapt and evaluate the reliability of the NVPQOL.

DESIGN AND SETTING

Observational cross-sectional study developed in a public university in Brazil.

METHODS

The translation, synthesis of translations, back-translation, expert committee, pre-testing and validation were carried out, resulting in a Portuguese-language version. The internal consistency, intra-rater and test-retest reliability and correlation between the total score of the Portuguese-language version of the NVPQOL and the domains of the World Health Organization Quality of Life-bref questionnaire were considered in the data analysis.

RESULTS

The instrument went through the process with testing on 104 pregnant women. Strong internal consistency (Cronbach's α: 0.95), strong intra-rater and test-retest reliability (P < 0.0; intraclass correlation coefficient: 0.89; confidence interval: 0.791-0.945) and strong correlation between the total score of the Portuguese-language version of the NVPQOL and the physical health domain of the World Health Organization Quality of Life-bref questionnaire (P < 0.01; R = -0.8) were observed.

CONCLUSION

The NVPQOL was translated, cross-culturally adapted and validated for the Portuguese language with satisfactory psychometric properties for assessing quality of life, especially in relation to physical health, among pregnant women with symptoms of nausea and vomiting in the first trimester of pregnancy.

Whole-body vibration in the reduction of the cellulite

OBJECTIVE

Evaluate the effects of the whole body vibration in improving of cellulite in the women's gluteal region.

METHODS

Controlled clinical trial performed with 42 women, with cellulite in the gluteal region, detected by means of clinical examination. After evaluation, the women were divided into two groups: Whole-Body Vibration (WBV_G) and control (C_G). The evaluations were performed at the beginning and the end of 10 sessions and superficial skin temperature, perimetry in the gluteal region, analysis of body contouring, analysis of improvement by blind reviewers and instrument of satisfaction, by numeric scale were investigated.

RESULTS

In the thermographic analysis, the WBV_G obtained significant increase of superficial skin temperature on the right (p = 0.02) and left (p = 0.02) gluteal region. There was no difference in intra- and intergroups in perimetry and the analysis of body contour. The WBV_G obtained a higher percentage of improvement by assessment of the blind reviewers (p = 0.003) and greater aesthetics satisfaction (p = 0.006), when compared to C_G.

CONCLUSION

WBV provided an improvement in the aspect of the cellulite when assessed by blind reviewers and greater participants' satisfaction, providing a significant increase in the superficial skin temperature in the gluteal region.

Análise intra e interavaliadores da projeção do centro de massa do corpo obtido por fotogrametria

RESUMO Para o ótimo controle postural, o centro de massa (COM) do corpo é uma variável que se projeta verticalmente entre os pés, dentro de uma base de suporte. Este estudo teve por objetivo avaliar a confiabilidade inter e intra-avaliadores da projeção do COM na base de sustentação, mensurada com auxílio do Software de Avaliação Postural (SAPO). Cinquenta e sete voluntárias foram avaliadas e todas foram submetidas ao registro fotográfico nas vistas anterior, lateral direita e esquerda, no mesmo instante temporal. As imagens foram entregues a dois examinadores, os quais utilizaram o SAPO. Para a análise estatística, foi utilizado o coeficiente de correlação intraclasse (ICC) e, para estimar a mínima mudança detectável (MMD), foi utilizado o erro padrão (EP). Os resultados demonstraram excelentes níveis de confiabilidade interexaminador e intraexaminador para assimetrias nos planos frontal, sagital e para a projeção do centro de gravidade no plano frontal e lateral (ICC>0,90; 95%IC>0,95; MDD entre 2,16 - 4,87). Os resultados do estudo demonstraram que a análise do COM obtida por meio do SAPO apresentou boa confiabilidade nas análises inter e intra-avaliadores.

Training through gametherapy promotes coactivation of the pelvic floor and abdominal muscles in young women, nulliparous and continents

Introduction and objectives:

Several studies have been investigated co-activation can enhance the effectveness of PFM training protocols allowing preventive and therapeutic goals in pelvic floor dysfunctions. The objective of the present study was to investigate if an abdominal-pelvic protocol of training (APT) using gametherapy would allow co-activation of PFM and transversus abdominis/oblique internal (TrA/OI) muscles.

Patients and methods:

Twenty-five nulliparous, continent, young females, with median age 24.76 (±3.76) years were evaluated using digital palpation (DP) of PFM and surface electromyography of PFM and TrA/OI simultaneously, during maximal voluntary contraction (MVC), alternating PFM and TrA/OI contraction requests. All women participated on a supervised program of APT using gametherapy, that included exercises of pelvic mobilization associated to contraction of TrA/OI muscles oriented by virtual games, for 30 minutes, three times a week, in a total of 10 sessions. Electromyographic data were processed and analyzed by ANOVA - analysis of variance.

Results:

When MVC of TrA/OI was solicited, it was observed simultaneous increase of electromyographic activity of PFM (p=0.001) following ATP. However, EMG activity did not change significantly during MVC of PFM.

Conclusion:

Training using gametherapy allowed better co-activation of pelvic floor muscles in response to contraction of TrA, in young nulliparous and continent women.

The effects of training by virtual reality or gym ball on pelvic floor muscle strength in postmenopausal women: a randomized controlled trial

Objective

To evaluate the effectiveness of abdominopelvic training by virtual reality compared to pelvic floor muscle training (PFMT) using a gym ball (a previously tested and efficient protocol) on postmenopausal women’s pelvic floor muscle (PFM) strength.

Method

A randomized controlled trial was conducted with 60 postmenopausal women, randomly allocated into two groups: Abdominopelvic training by virtual reality – APT_VR (n=30) and PFMT using a gym ball – PFMT_GB (n=30). Both types of training were supervised by the same physical therapist, during 10 sessions each, for 30 minutes. The participants’ PFM strength was evaluated by digital palpation and vaginal dynamometry, considering three different parameters: maximum strength, average strength and endurance. An intention-to-treat approach was used to analyze the participants according to original groups.

Results

No significant between-group differences were observed in most analyzed parameters. The outcome endurance was higher in the APT_VR group (p=0.003; effect size=0.89; mean difference=1.37; 95% CI=0.46 to 2.28).

Conclusion

Both protocols have improved the overall PFM strength, suggesting that both are equally beneficial and can be used in clinical practice. Muscle endurance was higher in patients who trained using virtual reality.

Abdominopelvic kinesiotherapy for pelvic floor muscle training: a tested proposal in different groups

INTRODUCTION AND HYPOTHESIS

This video's proposal was to present one of the pelvic floor muscle (PFM) training programs used in our research, and to study the effects of abdominopelvic kinesiotherapy on female PFM function.

METHODS

A total of 82 women participated in this study, 11 nulliparous, 13 primiparous pregnant, 20 primiparous postpartum and 38 postmenopausal women, who were evaluated first by digital palpation, then by either electromyography or vaginal dynamometry to investigate their PFM strength, followed by ICIQ UI-SF and ICIQ-OAB to evaluate urinary symptoms. This intervention protocol lasted for 60 min, three times a week, with a total of 10 sessions, and was supervised by a physiotherapist, using a gym ball, according to Marques and collaborators.

RESULTS

A significant increase in PFM strength was observed by digital palpation in all groups. This finding was confirmed by electromyography in both pregnant (p = 0.0001) and postpartum (p = 0.0001) groups, as well as in 20 of the 38 women from the postmenopausal group (p = 0.003) then by vaginal dynamometry (p = 0.02) in the rest of the women (18) from the same group, with a concomitant decrease in urinary symptoms (p < 0.05).

CONCLUSION

The abdominopelvic kinesiotherapy program promotes an increase in pelvic floor muscle strength and a decrease in urinary symptoms.

Virtual reality: a proposal for pelvic floor muscle training

INTRODUCTION AND HYPOTHESIS

This video's proposal was to present one of the pelvic floor muscle (PFM) training programs, used in our research, that we designed as a virtual reality intervention protocol and investigated its effects on PFM contractility.

METHODS

Two clinical, controlled and prospective studies were conducted, one with 19 nulliparous women without urinary symptoms, who were evaluated by both electromyography and digital palpation (DP) and another with 27 postmenopausal women with mixed urinary symptoms (assessed by both ICIQ UI-SF and ICIQ-OAB), evaluated by vaginal dynamometry and DP, with a total of 46 women in both studies. This protocol was designed so that the participant would play a video game, seated on a pressure base platform, while commanding it through her pelvic movements. Using a virtual reality game, five activities were performed during 30 min, twice a week, with a total of 10 sessions.

RESULTS

A significant increase in PFM strength was found in both the nulliparous (p = 0.0001) and the postmenopausal (p = 0.0001) groups of women, as ascertained by DP. A significant increase in postmenopausal women's muscle strength and endurance assessed by dynamometry (p = 0.05) and a concomitant decrease in their urinary symptoms, were observed.

CONCLUSION

This virtual reality program promoted an increase in PFM contractility and a decrease in postmenopausal urinary symptoms.

Intra and inter-rater reliability study of pelvic floor muscle dynamometric measurements

OBJECTIVE:

The aim of this study was to evaluate the intra and inter-rater reliability of pelvic floor muscle (PFM) dynamometric measurements for maximum and average strengths, as well as endurance.

METHOD:

A convenience sample of 18 nulliparous women, without any urogynecological complaints, aged between 19 and 31 (mean age of 25.4±3.9) participated in this study. They were evaluated using a pelvic floor dynamometer based on load cell technology. The dynamometric evaluations were repeated in three successive sessions: two on the same day with a rest period of 30 minutes between them, and the third on the following day. All participants were evaluated twice in each session; first by examiner 1 followed by examiner 2. The vaginal dynamometry data were analyzed using three parameters: maximum strength, average strength, and endurance. The Intraclass Correlation Coefficient (ICC) was applied to estimate the PFM dynamometric measurement reliability, considering a good level as being above 0.75.

RESULTS:

The intra and inter-raters' analyses showed good reliability for maximum strength (ICC_intra-rater1=0.96, ICC_intra-rater2=0.95, and ICC_inter-rater=0.96), average strength (ICC_intra-rater1=0.96, ICC_intra-rater2=0.94, and ICC_inter-rater=0.97), and endurance (ICC_intra-rater1=0.88, ICC_intra-rater2=0.86, and ICC_inter-rater=0.92) dynamometric measurements.

CONCLUSIONS:

The PFM dynamometric measurements showed good intra- and inter-rater reliability for maximum strength, average strength and endurance, which demonstrates that this is a reliable device that can be used in clinical practice.

A pelvic floor muscle training program in postmenopausal women: A randomized controlled trial

OBJECTIVES

The purpose of this study was to investigate if a specific pelvic floor muscle training (PFMT) program effectively increases pelvic floor muscle (PFM) contractility and decreases anterior pelvic organ prolapse (POP) as well as urogynecological symptoms, in postmenopausal women. The mean outcome measure of this study was the pelvic floor surface electromyography (sEMG) activity.

STUDY DESIGN

A clinical, randomized, blinded-assessor and controlled study was conducted with 46 postmenopausal women. Thirty women completed this study (mean age of 65.93 years), divided into two groups: Treatment Group - TG (n=18) and Control Group - CG (n=12). The evaluation was carried out using digital palpation, sEMG, pelvic organ prolapse quantification (POP-Q) as well as validated questionnaires by the International Consultation on Incontinence Questionnaires to investigate urogynecological symptoms. The treatment protocol consisted of 12 group sessions, twice a week, with 30 min of duration each. These data were then submitted to statistical analyses by the Statistical Analysis System for Windows software, with a significance level of 5%.

RESULTS

The pelvic floor muscle contractility increased after PFMT, evaluated by sEMG (p=0.003) and digital palpation (p=0.001), accompanied by a decrease in urinary symptoms (p<0.001 for ICIQ-OAB scores e 0.036 for ICIQ UI-SF) as well as anterior pelvic organ prolapse (p=0.03).

CONCLUSION

This preliminary study suggests that the applied PFMT program could be an effective way to increase PFM contractility, as well as to decrease both anterior pelvic organ prolapse and urinary symptoms, in postmenopausal women.

Are transversus abdominis/oblique internal and pelvic floor muscles coactivated during pregnancy and postpartum?

AIM

The aim of this study was to simultaneously evaluate both transversus abdominis/internal oblique (Tra/IO) and pelvic floor muscles (PFM) during isometric exercises in nulliparous, pregnant, and postpartum women.

METHODS

The study included 81 women divided into four groups: (G1) nulliparous women without urinary symptoms (n = 20); (G2) primigravid pregnant women with gestational age ≥24 weeks (n = 25); (G3) primiparous postpartum women after vaginal delivery with right mediolateral episiotomy (n = 19); (G4) primiparous postpartum women after cesarean section delivery, with 40 to 60 days of postpartum (n = 17). The assessment consisted of simultaneous surface electromyography (EMGs) of the PFM and Tra/IO, during three isometric maximum voluntary contractions.

RESULTS

Only nulliparous women presented significant simultaneous Tra/IO and PFM co-activation when asked to contract PFM (P = 0.0007) or Tra/IO (P = 0.00001).

CONCLUSIONS

There is co-activation of the transversus abdominis/internal oblique and the pelvic floor muscles in young, asymptomatic nulliparous women. This pattern was modified in primigravid pregnant and primiparous postpartum women regardless of the delivery mode.

Impact of delivery mode on electromyographic activity of pelvic floor: comparative prospective study

AIMS

Several studies evidenced the association between pregnancy, mode of delivery and genitourinary symptoms. However, there are still controversies about the role of mode of delivery in the prevention or aggravation of these symptoms. This study aimed to compare the impact of three distinct modes of delivery on pelvic floor muscle contractility.

METHODS

Seventy-five primiparous women were divided into three groups: (1) vaginal delivery with mediolateral episiotomy (n = 28); (2) elective cesarean section (n = 26); (3) emergency cesarean section (n = 21). All patients underwent vaginal digital examination, grading the muscle contractility from 0 to 5 and surface electromyography (EMG) of the pelvic floor during the last trimester of pregnancy and 45 days after delivery.

RESULTS

There was a significant increase in pelvic floor contractility in the elective cesarean section group, from 2.35 to 2.92 (P = 0.03), when compared to the vaginal delivery and emergency cesarean section groups. Analysis of electromyography data showed a significant reduction in maximum contraction of the pelvic floor after vaginal delivery, from 39.17 to 31.14 µV (P = 0.001), which was not observed in both cesarean section groups.

CONCLUSION

Vaginal delivery was associated with a decrease in pelvic floor muscle strength and endurance 45 days after delivery when compared to elective cesarean section as well as emergency cesarean section.

[Overactive bladder symptoms in pregnancy and puerperium: is there a relationship between the symptoms score and quality of life?]

INTRODUCTION AND OBJECTIVE

During pregnancy, hormonal change, increase in the body mass index and the pressure caused by the enlarged uterus over the bladder and pelvic floor, are some factors involved in lower urinary tract symptoms (LUTS). This study was made to evaluate the correlation between pregnancy and delivery way with LUTS.

MATERIAL AND METHOD

This open prospective study was carried out using the overactive bladder questionnaire short form (OABq-SF). A total of 60 patients enrolled this study. The mean age was 24 year, raging from 14 to 40 years. The patients were evaluated during the third trimester and 6 months after delivery. Statistical analysis of the OABq-SF scores was made using the Pearson method.

RESULTS

Mean OABq-SF score during pregnancy was 35.2 and 6 months after delivery decreased to15. Quality of life was 82.9 during pregnancy and increased to 88.4 at 6 month after delivery. Patient's perception, that is correlation, was 55.02 (p=0.0001) during pregnancy and 36.1% (p=0.0046). Clinical correlation index was 6.7%.

CONCLUSIONS

Our study demonstrated that in spite of LUTS being more important during pregnancy, there is no significant clinical correlation in patient's perception.

A combined study of behavior and Fos expression in limbic structures after re-testing Wistar rats in the elevated plus-maze

The elevated plus-maze is an animal model used to study anxiety. In a second session, rats show a reduction in the exploratory behavior even when the two sessions are separated by intervals as large as 7 days. The aim of the present study was to investigate whether the reduction in the exploratory behavior is maintained after intervals larger than 7 days. Additionally, we aimed at investigating eventual correlations between behaviors in the plus-maze and activation of limbic structures as measured by Fos protein expression after the second session. Rats were tested for 5 min in the elevated plus-maze and re-tested 3, 9 or 33 days later. Other groups were tested only once. The rat brains were processed for immunohistochemical detection of Fos protein. The results show a decrease in the open arms exploration in the second trial with intervals of 3, 9 and 33 days. The expression of Fos protein in the piriform cortex, septal nucleus and paraventricular hypothalamic nucleus in the groups tested with intervals of 9 and 33 days were statistically different from the other groups. The alterations observed in exploratory behavior in the second session in the plus-maze did not correlate with Fos expression. In conclusion, although the specific test conditions were sufficient to evoke behavioral alterations in exploration in the elevated plus-maze, they were enough to induce significant Fos protein expression in piriform cortex, septal nucleus and thalamic and hypothalamic paraventricular nuclei but not in other areas such as dorsomedial nucleus of the hypothalamus and amygdala nuclei, known to be also active participants in circuits controlling fear and anxiety.

Effects of under- and overcrowding on exploratory behavior in the elevated plus-maze

The present work investigated whether the number of rats housed in a cage affects exploration of an elevated plus-maze. Male Wistar-derived rats were kept 1, 2, 3, 4, 6, 8, 12, 16, or 24 to same size cages either for 1 or 14 days and tested in the elevated plus-maze. Rats kept 6 to a cage were arbitrarily considered controls because this is the housing condition adopted in many laboratories, ours included. In comparison to controls, 1-day housed rats kept 1, 2, 16, and 24 to a cage decreased the percentage of entries into the open arms. Similar decreases were also found in the time spent in the open arms, the only exception being the group with rats kept 16 to a cage which failed to show significant differences from the control group. Fourteen-day housed rats kept 1, 2, 16, or 24 to a cage decreased the percentage of entries and time spent in the open arms. We found plus-maze exploration to be similar in groups in which rats were kept from 4 to 12 to a cage. The present data indicate that anxiogenic effects resulting from under- and overcrowding should be taken into consideration in behavioral studies.

Flow measurements via two-particle azimuthal correlations in Au + Au collisions at sqrt [s(NN)]=130 GeV

Two-particle azimuthal correlation functions are presented for charged hadrons produced in Au+Au collisions at the Relativistic Heavy Ion Collider (sqrt [s(NN)]=130 GeV). The measurements permit determination of elliptic flow without event-by-event estimation of the reaction plane. The extracted elliptic flow values (v2) show significant sensitivity to both the collision centrality and the transverse momenta of emitted hadrons, suggesting rapid thermalization and relatively strong velocity fields. When scaled by the eccentricity of the collision zone epsilon, the scaled elliptic flow shows little or no dependence on centrality for charged hadrons with relatively low p(T). A breakdown of this epsilon scaling is observed for charged hadrons with pT >1.0 GeV/c.

Measurement of Lambda and Lambda(macro) particles in Au+Au collisions at the square root of S(NN) = 130 GeV

We present results on the measurement of Lambda and Lambda(macro) production in Au+Au collisions at square root of (S (NN) = 130 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. The transverse momentum spectra were measured for minimum bias and for the 5% most central events. The Lambda;/Lambda ratios are constant as a function of p(T) and the number of participants. The measured net Lambda density is significantly larger than predicted by models based on hadronic strings (e.g., HIJING) but in approximate agreement with models which include the gluon-junction mechanism.

Net charge fluctuations in Au + Au interactions at sqrt[s(NN)]=130 GeV

Data from Au + Au interactions at sqrt[s(NN)]=130 GeV, obtained with the PHENIX detector at the Relativistic Heavy-Ion Collider, are used to investigate local net charge fluctuations among particles produced near midrapidity. According to recent suggestions, such fluctuations may carry information from the quark-gluon plasma. This analysis shows that the fluctuations are dominated by a stochastic distribution of particles, but are also sensitive to other effects, like global charge conservation and resonance decays.

Centrality dependence of pi(+/-), K(+/-), p, and (-)p production from sqrt[s(NN)] = 130 GeV Au + Au collisions at RHIC

Identified pi(+/-), K(+/-), p, and (-)p transverse momentum spectra at midrapidity in sqrt[s(NN)] = 130 GeV Au+Au collisions were measured by the PHENIX experiment at RHIC as a function of collision centrality. Average transverse momenta increase with the number of participating nucleons in a similar way for all particle species. Within errors, all midrapidity particle yields per participant are found to be increasing with the number of participating nucleons. There is an indication that K(+/-), p, and (-)p yields per participant increase faster than the pi(+/-) yields. In central collisions at high transverse momenta (p(T) > or =2 GeV/c), (-)p and p yields are comparable to the pi(+/-) yields.

Transverse-mass dependence of two-pion correlations in Au+Au collisions at square root[s(NN)] = 130 GeV

Two-pion correlations in square root[s(NN)] = 130 GeV Au+Au collisions at RHIC have been measured over a broad range of pair transverse momentum k(T) by the PHENIX experiment at RHIC. The k(T) dependent transverse radii are similar to results from heavy-ion collisions at square root[s(NN)] = 4.1, 4.9, and 17.3 GeV, whereas the longitudinal radius increases monotonically with beam energy. The ratio of the outwards to sidewards transverse radii (R(out)/R(side)) is consistent with unity and independent of k(T).

Measurement of single electrons and implications for charm production in Au+Au collisions at square root[s(NN)] = 130 GeV

Transverse momentum spectra of electrons from Au+Au collisions at square root[s(NN)] = 130 GeV have been measured at midrapidity by the PHENIX experiment at the Relativistic Heavy Ion Collider. The spectra show an excess above the background from photon conversions and light hadron decays. The electron signal is consistent with that expected from semileptonic decays of charm. The yield of the electron signal dN(e)/dy for p(T) > 0.8 GeV/c is 0.025+/-0.004(stat)+/-0.010(syst) in central collisions, and the corresponding charm cross section is 380+/-60(stat)+/-200(syst) microb per binary nucleon-nucleon collision.

Suppression of hadrons with large transverse momentum in central Au+Au collisions at root square[s(NN)] = 130 GeV

Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 GeV/c<p(T)<5 GeV/c have been measured by the PHENIX experiment at RHIC in Au+Au collisions at root square[s(NN)] = 130 GeV. At high p(T) the spectra from peripheral nuclear collisions are consistent with scaling the spectra from p+p collisions by the average number of binary nucleon-nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary-scaled p+p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear-medium effect in central nuclear collisions at RHIC energies.

Measurement of the midrapidity transverse energy distribution from square root of [(s)NN] = 130 GeV Au + Au collisions at RHIC

The first measurement of energy produced transverse to the beam direction at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory is presented. The midrapidity transverse energy density per participating nucleon rises steadily with the number of participants, closely paralleling the rise in charged-particle density, such that <E(T)>/<N(ch)> remains relatively constant as a function of centrality. The energy density calculated via Bjorken's prescription for the 2% most central Au+Au collisions at square root[s(NN)] = 130 GeV is at least epsilon(Bj) = 4.6 GeV/fm(3), which is a factor of 1.6 larger than found at sqrt[s(NN)] = 17.2 GeV ( Pb+Pb at CERN).

Centrality dependence of charged particle multiplicity in Au-Au collisions at square root of (s)NN = 130 GeV

We present results for the charged-particle multiplicity distribution at midrapidity in Au-Au collisions at square root of [s(NN)] = 130 GeV measured with the PHENIX detector at RHIC. For the 5% most central collisions we find dN(ch)/d eta(vertical line eta = 0) = 622+/-1(stat)+/-41(syst). The results, analyzed as a function of centrality, show a steady rise of the particle density per participating nucleon with centrality.