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OBJECTIVE: This study aimed to explore the current opinion on the routes of hysterectomy amongst the members of the International Society for Gynaecologic Endoscopy (ISGE), as well as the perceptions of potential barriers that inhibit gynaecologists from offering a minimally invasive hysterectomies (MIHs) to their patients. STUDY DESIGN: An anonymous, electronic survey was designed, including the questions about the surgeon location and length of gynaecological practice, preferred approach to hysterectomy, approximate number of surgical cases performed during the year preceding the survey (2021), and potential barriers and contraindications to performing MIHs. It was validated by 12 practicing gynaecologists. Subsequently, the survey was sent to all practicing gynaecologists who are the members of the ISGE. RESULTS: We received a response from 159 members of ISGE (29 % response rate), of which 92 % with ≥ 5 years in practice since the completion of their residency training in Gynaecology and Obstetrics. When asked about the preferred route of hysterectomy for themselves or their relatives, 59 % chose total laparoscopic hysterectomy (TLH), 19 % vaginal hysterectomy (VH), 8 % chose laparoscopically-assisted vaginal hysterectomy (LAVH) and 5 % chose total abdominal hysterectomy (TAH). However, TAH was the most performed hysterectomy procedure undertaken by the respondents in the year preceding the survey. When asked about the main obstacles to performing MIHs, more than half of the respondents highlighted insufficient training during residency and insufficient surgical experience. Only 25 % of the responders acknowledged reading the ISGE guidelines on performing vaginal hysterectomy. CONCLUSIONS: Contrary to a full understanding of the benefits of MIHs, lack of training, as well as insufficient surgical experience and unawareness of existing evidence-based guidelines were the main reasons for the high rate of TAH among the ISGE members who participated in the study. All efforts should be directed at teaching VH and TLH techniques during residency, continuous acquisition of practical experience, and use of validated patient selection guidelines for MIH in daily clinical practice.
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Ginecologia , Laparoscopia , Feminino , Humanos , Histerectomia/métodos , Endoscopia , Histerectomia Vaginal/métodos , Ginecologia/educação , Inquéritos e QuestionáriosRESUMO
Sacrocolpopexy is considered as the "gold standard" for management of women with apical prolapse. Numerous technical variants are being practiced. The first aim of this survey was to determine the habits of practice of laparoscopic sacrocolpopexy (LSCP) in Europe. The second aim was to determine whether surgeons who perform laparoscopic pelvic organ prolapse (POP) repair are familiar with the practice of alternative techniques and with mesh-less laparoscopic treatment of prolapse. The questionnaire was designed by the Urogynaecology Special Interest Group of the European Society for Gynaecological Endoscopy (ESGE). All ESGE-members were invited by email to respond to this survey consisting of 54 questions divided in different categories. Following review of ESGE member's responses, we have highlighted the great heterogeneity concerning the practice of LSCP and important variability in performance of concomitant surgeries. Alternative techniques are rarely used in practice. Furthermore, the lack of standardisation of the many surgical steps of a laparoscopic sacrocolpopexy is mainly due to the lack of evidence. There is a need for training and teaching in both standard and newer innovative techniques as well as the reporting of medium and long-term outcomes of both standard laparoscopic sacrocolpopexy and any of its alternatives.
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A system of N two-level atoms cooperatively interacting with a photonic field can be described as a single giant atom coupled to the field with interaction strength âN. This enhancement, known as Dicke cooperativity in quantum optics, has recently become an indispensable element in quantum information technology. Here, we extend the coupling beyond the standard light-matter interaction paradigm, enhancing Dicke cooperativity in a terahertz metasurface with N meta-atoms. The cooperative enhancement is manifested through the hybridization of the localized surface plasmon resonance in individual meta-atoms and surface lattice resonance due to the periodic array. Furthermore, through engineering of the capacitive split-gap in the meta-atoms, we were able to enhance the coupling rate into the ultrastrong coupling regime by a factor of N. Our strategy can serve as a new platform for demonstrating effective control of fermionic systems by weak pumping, superradiant emission, and ultrasensitive sensing of molecules.
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PbTe crystals have a soft transverse optical phonon mode in the terahertz frequency range, which is known to efficiently decay into heat-carrying acoustic phonons, resulting in anomalously low thermal conductivity. Here, we studied this phonon via polarization-dependent terahertz spectroscopy. We observed softening of this mode with decreasing temperature, indicative of incipient ferroelectricity, which we explain through a model including strong anharmonicity with a quartic displacement term. In magnetic fields up to 25 T, the phonon mode splits into two modes with opposite handedness, exhibiting circular dichroism. Their frequencies display Zeeman splitting together with an overall diamagnetic shift with increasing magnetic field. Using a group-theoretical approach, we demonstrate that these observations are the result of magnetic field-induced morphic changes in the crystal symmetries through the Lorentz force exerted on the lattice ions. Thus, our Letter reveals a novel process of controlling phonon properties in a soft ionic lattice by a strong magnetic field.
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PURPOSE: Postoperative spotting is a frequent adverse symptom after laparoscopic supracervical hysterectomy (LSH). The conical excision (eLSH) reduces the postoperative spotting rate, but data in a larger collective are still rare and inconsistent. The influence of persistent bleeding on the anxious and depressive symptoms has not been analyzed yet. METHODS: 311 patients, who underwent a laparoscopic supracervical hysterectomy with conical excision (n = 163), or with straight cervical resection (n = 148) were included. Anxious and depressive symptoms and postoperative spotting were recorded before operation, at 3 month follow-up and at 1 year follow-up in both operative groups using a validated questionnaire (German version of Hospital Anxiety and Depression Scale, HADS-D) and additional questions concerning the frequency and impact of bleeding. Statistical analysis included the impairment of bleeding as well as its impact on depressive and anxious symptoms for both groups. RESULTS: 11.5% after eLSH and 15.5% after LSH reported spotting after 1 year. Supracervical hysterectomy significantly improves depressive and anxious symptoms at 3 and at 12 month follow-up for both groups (p < 0.001) independent on residual spotting. Patients with a preoperative continuous bleeding showed a maximum benefit independent on operative method. CONCLUSION: Laparoscopic supracervical hysterectomy has a positive effect on anxious and depressive symptoms in the short-term and intermediate-term follow-up. The conical excision of the cervical stump reduces postoperative spotting rate, but has no explicit advantage on symptoms of depression or anxiety, irrespective of residual postoperative spotting.
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Laparoscopia , Metrorragia , Ansiedade , Feminino , Humanos , Histerectomia/efeitos adversos , Histerectomia/métodos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Estudos Prospectivos , Resultado do TratamentoRESUMO
PURPOSE: Supracervical as well as total hysterectomy are considered to improve postoperative sexuality as well as quality of life, but the benefit of supracervical hysterectomy (LSH) is impaired in up to 20 percent by postoperative spotting. The aim of this study was to analyze the influence of a conical excision of the cervical stump during supracervical hysterectomy on the postoperative spotting rate and its influence on sexuality and in turn quality of life. METHODS: 321 Patients who underwent a laparoscopic supracervical hysterectomy with conical excision (extended laparoscopic supracervical hysterectomy, eLSH, n = 166, Dormagen hospital) or with straight cervical resection (laparoscopic supracervical hysterectomy, LSH, n = 133, MIC Clinics Berlin) were included. Sexual matters, quality of life parameters and additional questions were recorded before operation, at three months of follow up, and at one year of follow up in both groups using a validated questionnaire (German version of International Consultation on Incontinence Questionnaire Vaginal Symptoms Module, ICIQ_VS). Statistical analysis included the impact and impairment of bleeding on sexuality, quality of life in both groups and co-factors such as vaginal symptoms. RESULTS: 11.3% after eLSH and 15.5% after LSH reported spotting after 1 year. Supracervical hysterectomy significantly improves quality of life and sexuality and a conical excision of the remaining stump is associated with a lower but insignificantly reduced spotting rates. Postoperative spotting has no negative influence on sexual matter score of ICIQ_VS, but reduces the postoperative quality of life focusing on vaginal symptoms in a significant way. CONCLUSION: The improvement of ICIQ_VS scores after supracervical hysterectomy is independent of postoperative spotting, but the quality-of-life score is positively influenced by a reduction in the postoperative spotting rate.
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Laparoscopia , Metrorragia , Feminino , Humanos , Histerectomia/efeitos adversos , Laparoscopia/efeitos adversos , Estudos Prospectivos , Qualidade de Vida , Sexualidade , Resultado do TratamentoRESUMO
We have observed photoinduced negative optical conductivity, or gain, in the terahertz frequency range in a GaAs multiple-quantum-well structure in a strong perpendicular magnetic field at low temperatures. The gain is narrow band: it appears as a sharp peak (linewidth <0.45 meV) whose frequency shifts with applied magnetic field. The gain has a circular-polarization selection rule: a strong line is observed for hole-cyclotron-resonance-active polarization. Furthermore, the gain appears only when the exciton 1s state is populated, which rules out intraexcitonic transitions to be its origin. Based on these observations, we propose a possible process in which the stimulated emission of a terahertz photon occurs while two free excitons scatter into one biexciton in an energy and angular-momentum conserving manner.
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INTRODUCTION: Pectopexy, a laparoscopic method for prolapse surgery, showed promising results in previous transient testing by this group. It was shown that a single suture, yielding an ultimate load of 35 N, was equivalent to continuous suturing. This was demonstrated in an in vitro cadaver study. This transient data were used to establish an elastic stress-strain envelope. It was now possible to proceed to dynamic in vitro analysis of this surgical method to establish time to functional stability. METHODS: Cyclic testing of this fixation method was performed on human female embalmed cadaver (cohort 1) and fresh, non-embalmed cadaver (cohort 2) pelvises. The testing envelope was 5-25 N at a speed of 1 mm/s. 100 load regulated cycles were applied. RESULTS: 100 cycles were completed with each model; no overall system failure occurred. Steady state, i.e., functional stability was reached after 14.5 (± 2.9) cycles for the embalmed group and after 19.1 (± 7.2) cycles for the non-embalmed group. This difference was statistically significant p = 0.00025. CONCLUSION: This trial showed in an in vitro cyclic testing of the pectopexy method that functional stability may be achieved after no more than 19.1 cycles of load exposure. When remaining within the established load envelope of below 25 N, patients do not need to fear global fixation failure. Testing did demonstrate differences in non-embalmed and embalmed cadaver testing. Embalmed cadaver testing tends to underestimate time to steady state by 26.3%.
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Laparoscopia/métodos , Prolapso de Órgão Pélvico/cirurgia , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Cadáver , Feminino , Seguimentos , HumanosRESUMO
Ruddlesden-Popper halide perovskites are 2D solution-processed quantum wells with a general formula A2A'n-1M n X3n+1, where optoelectronic properties can be tuned by varying the perovskite layer thickness (n-value), and have recently emerged as efficient semiconductors with technologically relevant stability. However, fundamental questions concerning the nature of optical resonances (excitons or free carriers) and the exciton reduced mass, and their scaling with quantum well thickness, which are critical for designing efficient optoelectronic devices, remain unresolved. Here, using optical spectroscopy and 60-Tesla magneto-absorption supported by modeling, we unambiguously demonstrate that the optical resonances arise from tightly bound excitons with both exciton reduced masses and binding energies decreasing, respectively, from 0.221 m0 to 0.186 m0 and from 470 meV to 125 meV with increasing thickness from n equals 1 to 5. Based on this study we propose a general scaling law to determine the binding energy of excitons in perovskite quantum wells of any layer thickness.
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Using computer simulations, we study the phase diagram of a two-dimensional system of disk particles with three patches distributed symmetrically along the particle equator. The geometry of the particles is compatible with a honey-comb lattice at moderately low temperature and pressure, whereas it is expected that the system forms a close-packed triangular lattice at high temperature and pressure. The effect of patch size within the single bond per patch regime was investigated, and it was found that the topology of the phase diagram changes drastically with patch size. Interestingly, in particles with small patches (with a half opening angle of 10°), the fluid transforms upon increasing the pressure into a rather exotic phase that can be understood as a honey-comb lattice whose voids are filled continuously with additional particles that remain, on average, unbound. Eventually, all the voids are occupied so that particles are located at the positions of a triangular lattice, but only two thirds of the particles are orientationally ordered whereas the remaining one third can rotate almost freely as in a plastic crystal. At moderately low temperature, the fluid transforms into a nearly empty honey-comb lattice, whereas at high temperature it transforms directly into the almost filled lattice. Interestingly, for particles with big patches (with a half opening angle of 20°), the honey-comb and triangular lattices are separated by a liquid phase that remains stable down to fairly low temperatures. Less surprisingly, only particles with big patches exhibit an equilibrium gas-liquid separation.
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BACKGROUND: Abiraterone (ABI) is a major oral agent for the treatment of metastatic castration-resistant prostate cancer (mCRPC) patients but its systemic exposure is subject to a large inter-individual variability. We aimed to explore the relationship between ABI trough plasma concentration and prostate-specific antigen (PSA) response in mCRPC patients and to identify the critical determinants for its activity. PATIENTS AND METHODS: This is a monocentric prospective observational study in mCRPC patients treated with ABI. The plasmatic concentration of ABI at steady state was measured using liquid chromatography with fluorescence detection. The primary objective was to study the relationship between mean ABI plasma exposure (ABI Cmin) and 3-month PSA response. RESULTS: From 2012 to 2016, 61 mCRPC patients were eligible for pharmacokinetic/pharmacodynamic assessment. Thirty-eight patients experienced PSA response (62%, [confidence interval {CI} 95% 50-78]). In univariate analysis, ABI Cmin was 1.5-fold higher in responders: 12.0 ng/mL (CI 95% 9.4-15.6) versus 8.0 ng/mL (CI 95% 5.8-11.6; P = 0.0015). In multivariate analysis, only ABI Cmin was independently associated with PSA response (odds ratio = 1.12 [CI 95% 1.01-1.25], P = 0.004). By receiver operating characteristic analysis, the optimal threshold for ABI Cmin was 8.4 ng/mL. Progression-free survival (PFS) was significantly higher in patients with ABI Cmin above 8.4 ng/mL (hazard ratio 0.55, [CI 95% 0.31-0.99], 12.2 [CI 95% 9.2-19.5] versus 7.4 [CI 95% 5.5-14.7] months otherwise, P = 0.044). CONCLUSIONS: We showed that ABI trough concentration correlates with PSA response and PFS. Moreover, we could determine a cut-off value of plasmatic concentration for PSA response. Altogether, ABI concentration monitoring appears as a new approach to improve clinical outcome in mCPRC patients.
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Antagonistas de Androgênios/farmacocinética , Androstenos/farmacocinética , Antígeno Prostático Específico/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/sangue , Antagonistas de Androgênios/uso terapêutico , Androstenos/sangue , Androstenos/uso terapêutico , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Estudos Prospectivos , Neoplasias de Próstata Resistentes à Castração/sangueRESUMO
Experience gained in the risk assessment (RA) of genetically engineered (GE) crops since their first experimental introductions in the early nineties, has increased the level of familiarity with these breeding methodologies and has motivated several agencies and expert groups worldwide to revisit the scientific criteria underlying the RA process. Along these lines, the need to engage in a scientific discussion for the case of GE crops transformed with similar constructs was recently identified in Argentina. In response to this need, the Argentine branch of the International Life Sciences Institute (ILSI Argentina) convened a tripartite working group to discuss a science-based evaluation approach for transformation events developed with genetic constructs which are identical or similar to those used in previously evaluated or approved GE crops. This discussion considered new transformation events within the same or different species and covered both environmental and food safety aspects. A construct similarity concept was defined, considering the biological function of the introduced genes. Factors like environmental and dietary exposure, familiarity with both the crop and the trait as well as the crop biology, were identified as key to inform a construct-based RA process.
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Produtos Agrícolas/genética , Alimentos Geneticamente Modificados/normas , Engenharia Genética/normas , Plantas Geneticamente Modificadas , Argentina , Cruzamento , Qualidade de Produtos para o Consumidor/normas , Medição de RiscoRESUMO
INTRODUCTION: Pectopexy, a laparoscopic method for prolapse surgery, showed promising results in recent literature. Further improving this approach by reducing surgical time may decrease complication rates and patient morbidity. Since laparoscopic suturing is a time consuming task, we propose a single suture /mesh ileo-pectineal ligament fixation as opposed to the commonly used continues approach. METHODS: Evaluation was performed on human non-embalmed, fresh cadaver pelves. A total of 33 trials was performed. Eight female pelves with an average age of 75, were used. This resulted in 16 available ligaments. Recorded parameters were ultimate load, displacement at failure and stiffness. RESULTS: The ultimate load for the mesh + simplified single "interrupted" suture (MIS) group was 35 (± 12) N and 48 (± 7) N for the mesh + continuous suture (MCS) group. There was no significant difference in the ultimate load between both groups (p> 0.05). This was also true for displacement at failure measured at 37 (± 12) mm and 36 (±5) mm respectively. There was also no significant difference in stiffness and failure modes. CONCLUSION: Given the data above we must conclude that a continuous suture is not necessary in laparoscopic mesh / ileo-pectineal ligament fixation during pectopexy. Ultimate load and displacement at failure results clearly indicate that a single suture is not inferior to a continuous approach. The use of two single sutures may improve ligamental fixation. However, overall stability should not benefit since the surgical mesh remains the limiting factor.
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Laparoscopia/métodos , Ligamentos/cirurgia , Pelve/cirurgia , Técnicas de Sutura , Idoso , Fenômenos Biomecânicos , Cadáver , Feminino , Humanos , Prolapso de Órgão Pélvico/cirurgia , Telas Cirúrgicas , Suporte de CargaRESUMO
We have developed a single-shot terahertz time-domain spectrometer to perform optical-pump/terahertz-probe experiments in pulsed, high magnetic fields up to 30 T. The single-shot detection scheme for measuring a terahertz waveform incorporates a reflective echelon to create time-delayed beamlets across the intensity profile of the optical gate beam before it spatially and temporally overlaps with the terahertz radiation in a ZnTe detection crystal. After imaging the gate beam onto a camera, we can retrieve the terahertz time-domain waveform by analyzing the resulting image. To demonstrate the utility of our technique, we measured cyclotron resonance absorption of optically excited carriers in the terahertz frequency range in intrinsic silicon at high magnetic fields, with results that agree well with published values.
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Vemurafenib is a BRAF kinase inhibitor approved for first-line treatment of metastatic BRAF (V600) -mutant melanoma. However, data on the pharmacokinetic/pharmacodynamic (PK/PD) relationship are lacking. The aim of this prospective, multicenter study was to explore the PK/PD relationship for vemurafenib in outpatients with advanced BRAF-mutated melanoma. Fifty-nine patients treated with single-agent vemurafenib were prospectively analyzed. Vemurafenib plasma concentration (n = 159) was measured at days 15, 30, 60, and 90 after treatment initiation. Clinical and biological determinants (including plasma vemurafenib concentration) for efficacy and safety were assessed using Cox's model and multivariate stepwise logistic regression. Median progression-free survival (PFS) and overall survival were 5.0 (95 % confidence interval [95 % CI] 2.0-6.0) and 11.0 (95% CI 7.0-16.0) months, respectively. Twenty-nine patients (49 %) experienced any grade ≥3 toxicity and the most frequent grade ≥2 toxicity was skin rash (37 %). Severe toxicities led to definitive discontinuation in seven patients (12 %). Grade ≥2 skin rash was not statistically associated with better objective response at day 60 (p = 0.06) and longer PFS (hazard ratio 0.47; 95 % CI 0.21-1.08; p = 0.075). Grade ≥2 skin rash was statistically increased in patients with ECOG ≥ 1 (odds ratio 4.67; 95 % CI 1.39-15.70; p = 0.012). Vemurafenib concentration below 40.4 mg/L at day 15 was significantly associated with a shorter PFS (1.5 [0.5-5.5] vs. 4.5 [2-undetermined] months, p = 0.029). Finally, vemurafenib concentration was significantly greater in patients developing grade ≥2 rash (61.7 ± 25.0 vs. 36.3 ± 17.9 mg/L, p < 0.0001). These results suggest that early plasma drug monitoring may help identify outpatients at high risk of non-response or grade ≥ 2 skin rash.
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Neoplasias Encefálicas/tratamento farmacológico , Indóis/farmacocinética , Melanoma/tratamento farmacológico , Mutação/genética , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Proto-Oncogênicas B-raf/genética , Sulfonamidas/farmacocinética , Idoso , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Feminino , Seguimentos , Humanos , Indóis/uso terapêutico , Masculino , Melanoma/genética , Melanoma/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico , Sulfonamidas/uso terapêutico , Distribuição Tecidual , VemurafenibRESUMO
Molecular dynamics simulations and integral equation calculations of a simple equimolar mixture of diatomic molecules and monomers interacting via attractive and repulsive short-range potentials show the existence of pattern formation (microheterogeneity), mostly due to depletion forces away from the demixing region. Effective site-site potentials extracted from the pair correlation functions using an inverse Monte Carlo approach and an integral equation inversion procedure exhibit the features characteristic of a short-range attractive and a long-range repulsive potential. When charges are incorporated into the model, this becomes a coarse grained representation of a room temperature ionic liquid, and as expected, intermediate range order becomes more pronounced and stable.
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Simulação de Dinâmica Molecular , Líquidos Iônicos/química , Método de Monte Carlo , TemperaturaRESUMO
The J(1)-J(2) Ising model in the square lattice in the presence of an external field is studied by two approaches: the cluster variation method (CVM) and Monte Carlo simulations. The use of the CVM in the square approximation leads to the presence of a new equilibrium phase, not previously reported for this model: an Ising-nematic phase, which shows orientational order but not positional order, between the known stripes and disordered phases. Suitable order parameters are defined, and the phase diagram of the model is obtained. Monte Carlo simulations are in qualitative agreement with the CVM results, giving support to the presence of the new Ising-nematic phase. Phase diagrams in the temperature-external field plane are obtained for selected values of the parameter κ=J(2)/|J(1)| which measures the relative strength of the competing interactions. From the CVM in the square approximation we obtain a line of second order transitions between the disordered and nematic phases, while the nematic-stripes phase transitions are found to be of first order. The Monte Carlo results suggest a line of second order nematic-disordered phase transitions in agreement with the CVM results. Regarding the stripes-nematic transitions, the present Monte Carlo results are not precise enough to reach definite conclusions about the nature of the transitions.
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The behavior of a fluid with competing interaction ranges adsorbed in a controlled pore size disordered matrix is studied by means of grand canonical Monte Carlo simulations in order to analyze the effects of confinement. The disordered matrix model is constructed from a two-dimensional non-additive hard-sphere fluid (which shows close to its demixing critical point large fluctuations in the concentration), after a subsequent quenching of the particle positions and removal of one of the components. The topology of the porous network is analyzed by means of a Delaunay tessellation procedure. The porous cavities are large enough to allow for cluster formation, which is however somewhat hindered as a result of the confinement, as seen from the comparison of cluster size distributions calculated for the fluid under confinement and in the bulk. The occurrence of lamellar phases is impeded by the disordered nature of the porous network. Analysis of two-dimensional density maps of the adsorbed fluid for given matrix configurations shows that clusters tend to build up in specific locations of the porous matrix, so as to minimize inter-cluster repulsion.