Phase diagram of the NaCl-water system from computer simulations.

NaCl aqueous solutions are ubiquitous. They can crystallize into ice, NaCl, or NaCl · 2H2O depending on the temperature-concentration conditions. These crystallization transitions have important implications in geology, cryopreservation, or atmospheric science. Computer simulations can help understand the crystallization of these solids, which requires a detailed knowledge of the equilibrium phase diagram. We use molecular simulations in which we put at contact the solution with the solid of interest to determine points of the solid-solution coexistence lines. We follow two different approaches, one in which we narrow down the melting temperature for a given concentration and the other in which we equilibrate the concentration for a given temperature, obtaining consistent results. The phase diagram thus calculated for the selected model (TIP4P/2005 for water molecules and Joung-Cheatham for the ions) correctly predicts coexistence between the solution and ice. We were only able to determine NaCl · 2H2O-solution coexistence points at higher temperatures and concentrations than in the experiment, so we could not establish a direct comparison in this case. On the other hand, the model underestimates the concentration of the solution in equilibrium with the NaCl solid. Our results, alongside other literature evidence, seem to indicate that ion-ion interactions are too strong in the model. Our work is a good starting point for the improvement of the potential model and for the study of the nucleation kinetics of the solid phases involved in the phase diagram.

A multicentre, open-label, single-arm phase II trial of the efficacy and safety of sclerotherapy using 3% polidocanol foam to treat second-degree haemorrhoids (SCLEROFOAM).

BACKGROUND: The aim of the present study was to evaluate the efficacy and safety of 3% polidocanol foam for treating 2nd-degree haemorrhoids. METHODS: A multicentre, open-label, single-arm, phase 2 trial involving 10 tertiary referral centres for haemorrhodal disease (HD) was performed. Between January and June 2019, patients with 2nd-degree haemorrhoids were prospectively included in this study. The primary outcome was to establish the success rate after one sclerotherapy session in terms of complete resolution of bleeding episodes one week after the injection. The Hemorrhoidal Disease Symptom Score (HDSS), the Short Health Scale for HD (SHS-HD) score and the Vaizey incontinence score were used to assess symptoms and their impact on quality of life and continence. Pain after the procedure, subjective symptoms and the amount and type of painkillers used were recorded. Patients were followed up for 1 year. RESULTS: There were 183 patients [111 males; 60.7%, mean age 51.3 ± 13.5 (18-75) years]. Complete resolution of bleeding was reached in 125/183 patients (68.3%) at 1 week and the recurrence rate was 12% (15/125). Thirteen patients (7.4%) underwent a second sclerotherapy session, while only 1 patient (1.8%) had to undergo a third session. The overall 1-year success rate was 95.6% (175/183). The HDSS and the SHS score significantly improved from a median preoperative value of 11 and 18 to 0 and 0, respectively (p < 0.001). There were 3 episodes of external thrombosis. No serious adverse events occurred. CONCLUSIONS: Sclerotherapy with 3% polidocanol foam is a safe, effective, painless, repeatable and low-cost procedure in patients with bleeding haemorrhoids.

Resolution gain in space-time digital holography by self-assembling of the object frequencies.

Space-time digital holography (STDH) exploits the object motion to record the hologram in a hybrid ST domain. This representation adds new capabilities to conventional DH, e.g., unlimited field of view and variable phase shifting. This is the best candidate for imaging biological samples flowing in microfluidic channels. Here, we show that STDH is able to improve the spatial resolution as well. Different from other super-resolution approaches, stitching between holograms or their spectra is no longer required. Moreover, we introduce a new oblique STDH modality to record and process hybrid ST representations. This allows improving resolution in 2D with one single object scan, paving the way to the use of STDH for super-resolution imaging onboard microfluidic devices.

The proactive self-control of actions: Time-course of underlying brain activities.

Proactive brain control optimizes upcoming actions and inhibits unwanted responses. In the present event-related potential (ERP) study, participants freely decided in advance whether to respond or not to an upcoming stimulus, then prepared or not the action according to their decision; finally, a stimulus was delivered, and subjects had to respond (or not). During the decision-making stage, a prefrontal negativity raised bilaterally in case no-response was decided, reflecting the first brain signal of proactive inhibition. Simultaneously, slow activity raised over premotor cortices independently from the decision taken, and then raised during the preparation phase only in the case of response decision (as a sort of accelerator). When the decision was not to respond, the prefrontal activity remained sustained (as a sort of brake) and showed a right-lateralized distribution during the preparation phase. Overall, we described the time-course of a proactive accelerating-braking system regulating self-control of actions.

Meningococcal carriage in children and young adults in the Philippines: a single group, cross-sectional study.

This cross-sectional prevalence study investigates meningococcal carriage for the first time in a Southeast Asian population. Posterior pharyngeal swabs were collected between August 2013 and March 2014 from 937 healthy Filipinos aged 5-24 years attending school or university in Manila. Of these, 35 were found to be carriers giving an overall carriage prevalence of 3·7% [95% confidence interval (CI) 2·6-5·2]. Carriage was associated with age (P < 0·001) and was highest (9·0%, 95% CI 5·5-13·8) in subjects aged 10-14 years, but was comparatively low (<3%) in all other age groups considered. This suggests that an immunization programme in the Philippines designed to reduce carriage acquisition and induce herd immunity may require a vaccine dose before the age of 10 years. Serogroup B was most commonly carried (65·7%, 95% CI 47·8-80·9), with a small number of carriers for serogroups C, Y and W also present. Two individuals (5·7%, 95% CI 0·7-19·2) who were simultaneously carrying multiple serogroups were identified. This exploratory study provides valuable insight into the asymptomatic carriage of Neisseria meningitidis in a healthy subset of the Filipino population and illustrates the importance of generating local carriage data.

Self-propelling bacteria mimic coherent light decorrelation.

We show here that live e-coli bacterial culture, thanks to the self-propelling feature, can significantly reduce the coherent noise. In fact, the typical self-propelled drive of such microorganisms provides enough time diversity in speckle patterns. Optical properties of a bacteria suspension have been investigated and analyzed thus showing that it behaves as a quite good optical speckle decorrelation device. Samples with different bacteria densities have been studied. The decorrelation effect has been demonstrated by probing the imaging performance in through transmission in coherent microscope configuration.

Spatio-temporal scanning modality for synthesizing interferograms and digital holograms.

We investigate the spatio-temporal scanning of a single-pixel row for building up synthetic interferograms or digital holograms, shifted each other of a desired phase step. This unusual recording modality exploits the object movement to synthesize interferograms with extended Field of View and improved noise contrast. We report the theoretical formulation of the synthetizing recording process and experimental evidence of various cases demonstrating quantitative phase retrieval by adopting this intrinsic phase-shifting procedure. The proposed method could be particularly suited in all cases where the object shift is an intrinsic feature of the investigated system, as e.g. in microfluidics imaging.

Imaging through scattering microfluidic channels by digital holography for information recovery in lab on chip.

We tackle the problem of information recovery and imaging through scattering microfluidic chips by means of digital holography (DH). In many cases the chip can become opalescent due to residual deposits settling down the inner channel faces, biofilm formation, scattering particle uptake by the channel cladding or its damaging by corrosive substances, or even by condensing effect on the exterior channels walls. In these cases white-light imaging is severely degraded and no information is obtainable at all about the flowing samples. Here we investigate the problem of counting and estimating velocity of cells flowing inside a scattering chip. Moreover we propose and test a method based on the recording of multiple digital holograms to retrieve improved phase-contrast images despite the strong scattering effect. This method helps, thanks to DH, to recover information which, otherwise, would be completely lost.

Imaging live humans through smoke and flames using far-infrared digital holography.

The ability to see behind flames is a key challenge for the industrial field and particularly for the safety field. Development of new technologies to detect live people through smoke and flames in fire scenes is an extremely desirable goal since it can save human lives. The latest technologies, including equipment adopted by fire departments, use infrared bolometers for infrared digital cameras that allow users to see through smoke. However, such detectors are blinded by flame-emitted radiation. Here we show a completely different approach that makes use of lensless digital holography technology in the infrared range for successful imaging through smoke and flames. Notably, we demonstrate that digital holography with a cw laser allows the recording of dynamic human-size targets. In this work, easy detection of live, moving people is achieved through both smoke and flames, thus demonstrating the capability of digital holography at 10.6 µm.

Random resampling masks: a non-Bayesian one-shot strategy for noise reduction in digital holography.

Holographic imaging may become severely degraded by a mixture of speckle and incoherent additive noise. Bayesian approaches reduce the incoherent noise, but prior information is needed on the noise statistics. With no prior knowledge, one-shot reduction of noise is a highly desirable goal, as the recording process is simplified and made faster. Indeed, neither multiple acquisitions nor a complex setup are needed. So far, this result has been achieved at the cost of a deterministic resolution loss. Here we propose a fast non-Bayesian denoising method that avoids this trade-off by means of a numerical synthesis of a moving diffuser. In this way, only one single hologram is required as multiple uncorrelated reconstructions are provided by random complementary resampling masks. Experiments show a significant incoherent noise reduction, close to the theoretical improvement bound, resulting in image-contrast improvement. At the same time, we preserve the resolution of the unprocessed image.

AI-aided holographic flow cytometry for label-free identification of ovarian cancer cells in the presence of unbalanced datasets.

Liquid biopsy is a valuable emerging alternative to tissue biopsy with great potential in the noninvasive early diagnostics of cancer. Liquid biopsy based on single cell analysis can be a powerful approach to identify circulating tumor cells (CTCs) in the bloodstream and could provide new opportunities to be implemented in routine screening programs. Since CTCs are very rare, the accurate classification based on high-throughput and highly informative microscopy methods should minimize the false negative rates. Here, we show that holographic flow cytometry is a valuable instrument to obtain quantitative phase-contrast maps as input data for artificial intelligence (AI)-based classifiers. We tackle the problem of discriminating between A2780 ovarian cancer cells and THP1 monocyte cells based on the phase-contrast images obtained in flow cytometry mode. We compare conventional machine learning analysis and deep learning architectures in the non-ideal case of having a dataset with unbalanced populations for the AI training step. The results show the capacity of AI-aided holographic flow cytometry to discriminate between the two cell lines and highlight the important role played by the phase-contrast signature of the cells to guarantee accurate classification.

Effect of task complexity on motor and cognitive preparatory brain activities.

In the present study, we investigated scalp-recorded activities of motor and cognitive preparation preceding stimulus presentation in relatively simple and complex visual motor discriminative response tasks (DRTs). Targets and non-targets were presented (with equal probability) in both tasks, and the complexity of the task depended on the discrimination and categorization processing load, which was based on the number of stimuli used (two stimuli in the simple- and four in the complex-DRT, respectively). We recorded event-related potentials (ERPs) in 16 participants in simple-DRT and 16 participants in complex-DRT. At the behavioral level, the performance was faster and more accurate in simple-DRT. Two pre-stimulus ERPs were considered: the central Bereitschaftspotential (BP) and the prefrontal negativity (pN). Both components showed earlier onset and larger amplitude in the complex-DRT. Overall, the simple-DRT required less motor and cognitive preparation in premotor and prefrontal areas compared to the complex-DRT. Present findings also suggest that the pN component was not reported in previous studies, likely because most ERP literature focusing on pre-stimulus ERP used simple-DRTs, and with such a task the pN amplitude is small and can easily go undetected.

Modality-specific sensory readiness for upcoming events revealed by slow cortical potentials.

Human brain activity allows to anticipate future events and to prepare the next action accordingly; consistently, event-related potential (ERP) studies found action preparatory brain activities in the premotor and prefrontal cortex. In the present study, we investigated the preparatory activity in the sensory cortical regions. Slow cortical potentials were recorded during passive tasks, i.e., subjects expected for a sensory stimulus and no motor or cognitive response were required. In particular, we tested the hypothesis that perceptual anticipatory cortical mechanisms were modality specific. Three groups of 21 young adults underwent passive perceptual tasks in different sensory modalities (visual, auditory, or somatosensory). We confirmed the presence of a visual negativity (vN) component for the visual modality starting about 800 ms before stimulus with source in extrastriate areas and we found novel modality-specific sensory readiness components for the auditory and somatosensory modalities. The auditory positivity (aP) started about 800 ms before stimulus with source in bilateral auditory cortices and the somatosensory negativity (sN) started about 500 ms before stimulus with source in the somatosensory secondary cortex, contralateral to the stimulated hand. The scalp topography and intracranial sources of these three slow preparatory activities were mirrored with inverted polarity at early post-stimulus stage evoking the well-known visual P1, auditory N1, and somatosensory P100 components. Present findings contribute to widening the family of slow wave preparatory components, providing evidence about the relationship between top-down and bottom-up processing in sensory perception.

Females are more proactive, males are more reactive: neural basis of the gender-related speed/accuracy trade-off in visuo-motor tasks.

In the present study, we investigated neural correlates associated with gender differences in a simple response task (SRT) and in a discriminative response task (DRT) by means of event-related potential (ERP) technique. 120 adults participated in the study, and, based on their sex, were divided into two groups matched for age and education level. Behavioral performance was assessed with computing response speed, accuracy rates and response consistency. Pre- and post-stimulus ERPs were analyzed and compared between groups. Results indicated that males were faster than females in all tasks, while females were more accurate and consistent than males in the more complex tasks. This different behavioral performance was associated with distinctive ERP features. In the preparation phase, males showed smaller prefrontal negativity (pN) and visual negativity (vN), interpreted as reduced cognitive preparation to stimulus occurrence and reduced reliance on sensory proactive readiness, respectively. In the post-stimulus phase, gender differences were present over occipital (P1, N1, P2 components) and prefrontal (pN1, pP1, pP2 components) areas, suggesting allocation of attentional resources at distinct stages of information processing in the two groups. Overall, the present data provide evidence in favor of a more proactive and cautious cognitive processing in females and a more reactive and fast cognitive processing in males. In addition, we confirm that (1) gender is an important variable to be considered in ERP studies on perceptual processing and decision making, and (2) the pre-stimulus component analysis can provide useful information concerning neural correlates of upcoming performance.

Fermented lactotripeptides-containing milk lowers daytime blood pressure in high normal-to-mild hypertensive subjects.

This study shows that consumption of fermented lactotripeptides (LTPs)-containing milk may have an acute daytime effect on blood pressure that appeared sustained with daily intake over a period of 4 weeks. Angiotensin 1-converting enzyme (ACE) inhibition by LTPs could not be confirmed in plasma.

Transcutaneous electrical nerve stimulation to treat vestibulodynia: a randomised controlled trial.

OBJECTIVE: To assess the efficacy of transcutaneous electrical nerve stimulation (TENS) in the treatment of vestibulodynia. DESIGN: Double-arm randomised placebo-controlled trial. SETTING: An outpatient department for vulval disease. POPULATION: Forty women with vestibulodynia, a vestibular discomfort mostly reported as a burning pain, occurring in the absence of relevant visible findings or a specific, clinically identifiable, neurological disorder. METHODS: Twice a week active TENS or sham treatment were delivered through a vaginal probe via a calibrated dual channel YSY-EST device. Women of both groups underwent 20 treatment sessions. MAIN OUTCOME MEASURES: Visual analogue scale (VAS), the short form of the McGill-Melzack Pain Questionnaire (SF-MPQ), the Marinoff Scale for dyspareunia and the Female Sexual Function Index questionnaire (FSFI) were assessed at baseline, at the end of treatment and at follow up 3 months after the end of treatment. RESULTS: The VAS and SF-MPQ scores (6.2 +/- 1.9 and 19.5 +/- 11.9 before treatment, respectively) improved significantly in the active TENS group (2.1 +/- 2.7, P= 0.004 and 8.5 +/- 10.7, P= 0.001, respectively), but not in the placebo group. The Marinoff dyspareunia scale and the FSFI also showed a significant improvement. CONCLUSIONS: TENS is a simple, effective and safe short-term (3 months) treatment for the management of vestibulodynia.

Diet assessment and the screening for osteoporosis: a survey in a healthy menopause population.

AIM: The aim of this study was to investigate about diet assessment in the screening for osteoporosis. METHODS: In 1,441 women (group A, mean age 53.5 years, mean time from menopause 3.92(+/-4.33)] the number of daily/weekly servings/cups of different foods has been collected. In 71 women (group B, mean age 59 years, mean time from menopause 6 years) diet was assessed through a detailed questionnaire. Demographic and clinical data and dietary habits were related to bone mineral density (BMD) values, using Student t-test and the chi2 test. RESULTS: Group A: borderline/reduced BMD 40%, the percentage increasing with age and the duration of menopause (P<0.001). BMI within normal range 56.28%. BMD values were positively associated with Body Mass Index (BMI, P<0.001), education level (P<0.005), job (P<0.01), oral contraceptives use (P<0.001), negatively with family history of osteoporosis (P<0.05). BMD values showed a positive relation with the number of eggs per week (P<0.05), positive not significant trends were observed with dairy products, vegetables, red and white meat intake. A low/reduced BMD was related to low calcium food intake in less than 50% of the women. Group B: borderline/reduced BMD 55%; BMD showed positive trends, not significant, with daily calcium intake, BMI, physical exercise. Estimated calcium intake less than 700 mg/day was found in 33% of the sample. CONCLUSION: Diet assessment is not useful in the screening for osteoporosis. In women with borderline or reduced BMD, diet assessment helps to detect those at low calcium intake who need calcium supplementation, alone or in combination with other treatments.

Weak proactive cognitive/motor brain control accounts for poor children's behavioral performance in speeded discrimination tasks.

BACKGROUND: Motor and inhibitory control rely on frontal cortex activity, which is known to reach full maturation only in late adolescence. The development of inhibitory control has been studied using event-related potentials (ERP), focusing on reactive processing (i.e. the N2 and the P3 components). Scarce information exists concerning pre-stimulus activity as that represented by the Bereinshafstpotential (BP) and by the prefrontal negativity (pN). Further, no literature exists concerning the post-stimulus components originating within the anterior insula (pN1, pP1, pP2). This study aims at associating children performance with these motor-cognitive processing in frontal brain areas. METHODS: High-resolution EEG recordings were employed to measure ERPs from 18 children (12 years old) and 18 adults (28 years old) during a visuo-motor discriminative response task. Response time (RT), commission (CE) and omission errors, and RT variability were compared between groups. At brain level, two pre-stimulus (BP and pN) and seven post-stimulus (P1; pN1; N1; pP1; N2; pP2; P3) ERP components were compared between groups. RESULTS: Children showed slower and more variable RTs and poorer inhibition (higher CEs) than adults. At electrophysiological level, children presented smaller BP and pN. After stimulus onset, children showed lower amplitude of N1, pP1, P3, and pP2 components. The P1, pP1, N2 and P3 were delayed compared to adults. CONCLUSIONS: Our results demonstrate that children are characterized by less intense task-related proactive activities in frontal cortex, which may account for subsequent poor and delayed reactive processing and, thus, for inaccurate and slow performance.

Exercise-related cognitive effects on sensory-motor control in athletes and drummers compared to non-athletes and other musicians.

Both playing a musical instrument and playing sport produce brain adaptations that might affect sensory-motor functions. While the benefits of sport practice have traditionally been attributed to aerobic fitness, it is still unknown whether playing an instrument might induce similar brain adaptations, or if a specific musical instrument like drums might be associated to specific benefits because of its high energy expenditure. Since the aerobic costs of playing drums was estimated to be comparable to those of average sport activities, we hypothesized that these two groups might show both behavioral and neurocognitive similarities. To test this hypothesis, we recruited 48 young adults and divided them into four age-matched groups: 12 drummers, 12 athletes, 12 no-drummer musicians and 12 non-athletes. Participants performed a visuo-motor discriminative response task, namely the Go/No-go, and their cortical activity was recorded by means of a 64-channel electroencephalography (EEG). Behavioral performance showed that athletes and drummers were faster than the other groups. Electrophysiological results showed that the pre-stimulus motor preparation (i.e. the Bereitschaftspotential or BP) and attentional control (i.e., the prefrontal negativity or pN), and specific post-stimulus components like the P3 and the pP2 (reflecting the stimulus categorization process) were enhanced in the athletes and drummers' groups. Overall, these results suggest that playing sport and drums led to similar benefits at behavioral and cognitive level as detectable in a cognitive task. Explanations of these findings, such as on the difference between drummers and other musicians, are provided in terms of long-term neural adaptation mechanisms and increased visuo-spatial abilities.

Tibolone in the treatment of menopause: compliance, efficacy and safety in a ten year experience.

AIM: To assess tibolone compliance, efficacy and safety in everyday clinical practice a non-randomized, prospective, cohort clinical study was carried out. METHODS: One hundred and fifty post-menopausal women aged 48 to 73 years were prescribed tibolone: 72 of them were treated for 36.4 months, 55 terminated treatment after less than 1 year, while 23 never took the tablets after seeking for menopause counseling and having agreed upon the treatment. We examined: endometrial thickness and histology, total cholesterol, triglycerides, fibrinogen, AST, ALT, gamma-gt, and the body weight. RESULTS: Side effects were the main causes of withdrawal (32%), and insufficient therapeutic effect and adverse events for a small number of cases (5.5% and 4.7% respectively), while various causes (fear of cancer, missing tablets, family doctor or other specialist's advice, remission of symptoms) were responsible for terminating treatment after extended periods. Laboratory findings showed a favorable trend; only the (GT showed slightly higher mean values, although within a normal range. On average, weight during treatment increased of 1.5 kg, and endometrial thickness grew of 1.3 mm in a mean time of 34.5 months of observation. An average of 2.3%/year increase of bone mineral density was reported, though bone mass didn't improve in some patients. CONCLUSIONS: Different causes of terminating treatment are related to the length of treatment, side effects being the main reason for early withdrawals, efficacy on symptoms or medical advice or fear of treatment for extended periods of time. Effectiveness on bone mass, safety as resulting from endometrial thickness and laboratory measures are confirmed. It is suggested to enhance follow-up accuracy and reinforce counseling as measures to improve compliance.