352 research outputs found
Increasing trap stiffness with position clamping in holographic optical tweezers
We present a holographic optical tweezers system capable of position clamping multiple particles. Moving an optical trap in response to the trapped object's motion is a powerful technique for optical control and force measurement. We have now realised this experimentally using a Boulder Nonlinear Systems Spatial Light Modulator (SLM) with a refresh rate of 203Hz. We obtain a reduction of 44% in the variance of the bead's position, corresponding to an increase in effective trap stiffness of 77%. This reduction relies on the generation of holograms at high speed. We present software capable of calculating holograms in under 1ms using a graphics processor unit. © 2009 Optical Society of America
Exploring livelihood strategies employed by women street food vendors in Gaborone, Botswana.
Magister Artium (Development Studies) - MA(DVS)The informal economy has continued to increase in developing countries, giving jobs and income to marginalised groups, the majority being women. The rise of the informal sector is perpetuated by exclusionary social policies and the continued increase in unemployment. In Botswana, street food vending, the most visible form of the informal sector trading, has evolved to be a survivalist activity that women populate. Increasing poverty levels, gender inequalities, and high unemployment rates have resulted in poor urban women being vulnerable to the stresses and shocks caused by these factors. Street food vending is therefore pursued by women to mitigate their vulnerability. Additionally, street food vending allows for more flexible working hours, thus accommodating women’s community, household, and productive roles. Despite women’s substantial contribution to Botswana’s informal economy, the government has not done much to support them
The potential use of crushed waste glass as a sustainable alternative to natural and manufactured sand in geotechnical applications
The increasing price and diminishing reserves of construction sand encourage a need to develop its sustainable and cost-effective replacement, helping the transition towards a circular economy. Waste glass is a derivative of natural sand and could potentially show similar geotechnical behaviour. Using crushed waste glass (CWG) as an alternative to traditional sand would potentially offer a double-duty benefit by helping to address the geo-environmental challenges of natural sand depletion and disposal of ever-increasing waste glass, together. This study investigated the geotechnical, mineralogical and morphological behaviour of CWG and compared it with that of natural sand (NS) and manufactured sand (MS). The geotechnical characterisation results showed that the behaviour of CWG is similar to the other two sands studied, with CWG showing the highest permeability and abrasion resistance. Surprisingly, the shear strength testing showed that the friction angle of CWG was higher under saturated conditions than under dry conditions, indicating the stability of CWG under saturated conditions. The mineralogical analysis was conducted using x-ray fluorescence (XRF) spectroscopy and revealed that silica is the dominant mineral in all three materials, indicating a similarity in their chemical composition. The morphological analysis was performed to quantify the particle shape of each material in terms of roundness index using digital images obtained through an optical microscope. The results demonstrated that MS showed the highest particle angularity, followed by CWG and NS. Overall, it was concluded that CWG could potentially act as a next-generation alternative and smart geomaterial, replacing traditional sands in several geotechnical applications
Transumbilical versus transvaginal retrieval of surgical specimens at laparoscopy: a randomized trial.
Objective
We sought to compare transumbilical (TU) and transvaginal (TV) route for retrieval of surgical specimens at laparoscopy.
Study design
Women scheduled for a laparoscopic resection of an adnexal mass were randomized to have their surgical specimen removed either through a posterior colpotomy (n = 34) or the umbilical port site (n = 32). Group allocation was concealed from patients and bedside clinicians. The primary outcome was postoperative incisional pain assessed by a 10-cm visual analog scale at 1, 3, and 24 hours after surgery.
Results
TV retrieval caused less postoperative pain than TU specimen extraction at each time point (visual analog scale score at 1 hour: 2.6 \ub1 2.9 vs 1.2 \ub1 2.0, P = .03; at 3 hours: 2.4 \ub1 2.0 vs 1.4 \ub1 2.0, P = .02; and at 24 hours: 1.1 \ub1 1.5 vs 0.5 \ub1 1.4, P = .02). A higher proportion of women in the TU group than in the TV group indicated the umbilicus as the most painful area at 1 and 3 hours postoperatively. Two months after surgery, the participants scored similarly as to their overall satisfaction, cosmetic outcome, and dyspareunia upon resumption of intercourse.
Conclusion
A TV approach for specimen removal after laparoscopic resection of adnexal masses offers the advantage of less postoperative pain than TU retrieva
Kaolin clay reinforced with a granular column containing crushed waste glass or traditional construction sands
Installation of granular columns is a cost-effective and versatile in situ technique to improve the shear strength, settlement, and drainage behaviour of weak soils. It involves backfilling vertical boreholes in the ground with granular materials stiffer than the native soil, such as stone or compacted sand. However, the massive use and overexploitation of sand and natural aggregates have depleted their reserves in recent decades, causing damage to the environment, creating sand shortages and skyrocketing their price. Hence, it is essential to develop a sustainable alternative to natural aggregates to construct granular columns. The ever-increasing stockpiles of waste glass could be a potential replacement for natural sand in several geotechnical construction applications, noting that both materials have a similar chemical composition. Using crushed waste glass (CWG) as an alternative to traditional natural and manufactured (quarried) sands in granular columns could offer a multi75 pronged benefit by recycling non-biodegradable waste (glass) and by conserving a depleting natural resource (sand). Using a large direct shear (LDS) machine, this study investigated the shear strength behaviour of kaolin (to represent a typical weak soil) reinforced with a central granular column. Three different materials were separately used to backfill the column, including natural sand (NS), manufactured sand (MS) and CWG. The results revealed that the geocomposites containing the CWG column have the highest peak friction angle and relatively greater shear strength under high normal stresses, favouring the potential use of CWG as a green alternative to traditional sands in backfilling granular columns, ultimately supporting resource conservation, waste recycling and the paradigm shift towards a circular economy
Does the polydimethylsiloxane urethral injection (Macroplastique®) improve sexual function in women, in fertile age, affected by stress urinary incontinence?
Background and Objectives: Stress urinary incontinence (SUI) negatively affects women's quality of life, including sexual function. The aim of the current study was to evaluate the effect of polydimethylsiloxane (Macroplastique(R)) on sexual function in women of fertile age affected by SUI. Materials and Methods: Single-center prospective study. Sexually active women of fertile age with symptoms of pure SUI, which were urodynamically proven, were submitted to intraurethral Macroplastique(R) injection. At 6-months follow-up, their sexual function was evaluated with Female Sexual Function Index (FSFI), while the SUI cure rate was objectively assessed through a negative stress test and subjectively by a Patient Global Impression of Improvement (PGI-I) score < 3. The difference of coital incontinence prevalence was assessed between the baseline and the 6-month follow-up. Peri- and postoperative complications of Macroplastique(R) injection were recorded and classified according to the Clavien-Dindo system. Results: Twenty-one women fulfilled inclusion criteria and were submitted to Macroplastique(R) procedure. The concerning sexual function, desire, satisfaction, and overall FSFI score significantly improved. Since other domains were less impaired at the baseline, we could not assess significant improvement for all of them. We observed a complete regression of coital incontinence (0/21, 0%) in comparison with the baseline (5/21, 23.8%; p = 0.04). The objective SUI cure rate was 76% (16/21), while the subjective SUI cure rate was 80.9% (17/21). One woman developed de novo overactive bladder, and two women developed postoperative voiding dysfunction (self-solved in 24 h). Conclusions: The Macroplastique(R) urethral injection was demonstrated to be safe and effective in improving sexual function in sexually active women of fertile age affected by pure SUI, urodinamically proven at 6-months follow-up
Cognitive correlates of neuroimaging abnormalities in the onset of schizophrenia : A case report
Increasing evidence shows that cognitive impairment and brain abnormalities can appear early in the first episodes of schizophrenia, but it is currently debated how brain changes can correlate with clinical presentation of schizophrenic patients. Of note, this report describes the case of a young schizophrenic male presenting parietal magnetic resonance/positron emission tomography abnormalities and cognitive impairment, documented by specific neuropsychological tests. In our knowledge only few studies have investigated if neuropsychological abnormalities could be concomitant with both structural and functional neuroimaging. This case shows that impairment in specific cognitive domains is associated with structural/functional brain abnormalities in the corresponding brain areas (frontal and parietal lobes), supporting the hypothesis of disconnectivity, involving a failure to integrate anatomical and functional pathways. Future research would define the role of cognitive impairment and neurodegeneration in psychiatric nosography and, in particular, their role in the early phases of illness and long-term outcome of schizophrenic patients
Randomised Controlled Trials Assessing the Clinical Value of Urodynamic Studies: A Systematic Review and Meta-analysis
Context: The role of urodynamic studies (UDSs) in the diagnosis of lower urinary tract symptoms (LUTS) is crucial. Although expert statements and guidelines underline their value for clinical decision-making in various clinical settings, the academic debate as to their impact on patient outcomes continues. Objective: To summarise the evidence from all randomised controlled trials assessing the clinical usefulness of UDS in the management of LUTS. Evidence acquisition: For this systematic review, searches were performed without language restrictions in three electronic databases until November 18, 2020. The inclusion criteria were randomised controlled study design and allocation to receive UDS or not prior to any clinical management. Quality assessment was performed by two reviewers independently, using the Cochrane Collaboration's tool for assessing the risk of bias. A random-effect meta-analysis was performed on the uniformly reported outcome parameters. Evidence synthesis: Eight trials were included, and all but two focused on women with pure or predominant stress urinary incontinence (SUI). A meta-analysis of six studies including 942 female patients was possible for treatment success, as defined by the authors (relative risk 1.00, 95% confidence interval: 0.93–1.07), indicating no difference in efficacy when managing women with UDS. Conclusions: Although UDSs are not replaceable in diagnostics, since there is no other equivalent method to find out exactly what the lower urinary tract problem is, there are little data supporting its impact on outcomes. Randomised controlled trials have focussed on a small group of women with uncomplicated SUI and showed no added value, but these findings cannot be extrapolated to the overall patient population with LUTS, warranting further well-designed trials. Patient summary: Despite urodynamics being the gold standard to assess lower urinary tract symptoms (LUTS), as it is the only method that can specify lower urinary tract dysfunction, more studies assessing the clinical usefulness of urodynamic studies (UDSs) in the management of LUTS are needed. UDS investigation is not increasing the probability of success in the treatment of stress urinary incontinence
Methodological study to evaluate the psychometric properties of FACIT-CD in a sample of Brazilian women with cervical intraepithelial neoplasia
Background: The occurrence of cervical intraepithelial neoplasia (CIN) is associated with changes in health-related quality of life, including psychological factors, such as fear and shame, and changes in sexuality and sexual satisfaction, such as decreased sexual desire and frequency of sexual intercourse. Personal relationships are the most affected because CIN is sexually transmitted and many women tend to blame their partner for disease transmission. The aim of this study was to evaluate the psychometric properties of the FACIT-CD questionnaire in Brazilian women diagnosed with CIN.
Methods: The properties of the FACIT-CD questionnaire were tested on a sample of 439 women seen at the Department of Prevention of Barretos Cancer Hospital, including 329 patients who were diagnosed with CIN and 110 women who were not diagnosed with the disease. The analysed parameters included internal consistency (Cronbach's alpha), reproducibility (intraclass correlation coefficient), structural validity, convergent validity (correlation with the SF-12 and EORTC QLQ-CX24 questionnaires), discriminant validity (according to disease status, and self-rating of health), sensitivity, and responsiveness.
Results: The Cronbach alpha values of the FACIT-CD scales were higher than 0.70 with the exception of the relationship scale (0.66). The FACIT-CD reproducibility was satisfactory, with variation in the intraclass correlation coefficients ranging between 0.50 and 0.83, although the 95% confidence interval (CI) was lower than 0.40 (0.33-0.64) on the treatment satisfaction scale. Regarding structural validity, only one item on the physical well-being scale was not kept in the original domain. The expected correlations between the FACIT-CD and SF-12 were not confirmed, whereas the correlations between the FACIT-CD and EORTC QLQ-CX24 were confirmed. The questionnaire was able to discriminate the groups according to disease status and self-rating of health. The sensitivity was low for the relationship scale and moderate for the other scales. The responsiveness of the FACIT-CD questionnaire varied between the groups that denominate the self-perception of health as no change, improvement or worsening.
Conclusion: Our results are encouraging and indicate that the FACIT-CD questionnaire is a promising tool for the analysis of the quality of life of women with CIN.The postdoctoral fellowship was supported by Sao Paulo Research Foundation (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo - FAPESP, Sao Paulo, Brazil). Process number: FAPESP 2014/10158-3. The funding body had no role in the design of the study and collection, analysis and interpretation of data and in writing the manuscript.info:eu-repo/semantics/publishedVersio
- …