Wet chemical synthesis of TGA capped Ag2S nanoparticles and their use for fluorescence imaging and temperature sensing in living cells.

In this work, we describe a simple wet chemical route for preparing silver sulfide nanoparticles (Ag2S) encapsulated with thioglycolic acid (TGA). By using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray (EDS) microanalysis, transmission electron microscopy (TEM), and dynamic light scattering (DLS), we have found that these nanoparticles were enrobed by TGA molecules and they have an Ag/S ratio nearly equal to 2.2 and a nearly spherical shape with two average size populations. Photoluminescence (PL) spectroscopy has shown that these nanoparticles are highly luminescent, photostable and photobleaching resistant and they emit in the first biologic window with a band peaking in the NIR region at 915 nm. We have demonstrated through a 3-(4,5-dimethyl-thiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay protocol and using U-87 MG human living cells that these nanoparticles are biocompatible with a viability ratio higher than 80% for a concentration equal to 100 µg mL-1. By investigating the effect of pH, ionic strength and thermal quenching on the PL emission, we have shown that these nanoparticles provide a convenient stable tool to measure temperature in the biological range with a relative thermal sensitivity higher than 5% per °C and they may be used as suitable fluorescent probes for living cell imaging and intracellular temperature mapping.

Allogenic stem cells for Crohn's anal fistulas: Treating early improves the deep remission rate.

AIM: The aim of this study was to evaluate the real-life clinical and radiological efficacy of darvadstrocel injection into complex perianal fistulas in Crohn's disease. Secondary endpoints were to assess symptomatic efficacy, adverse effects and factors associated with complete combined clinical-radiological response (deep remission). METHODS: After marketing the product in France, all first patients treated consecutively were included. A complete clinical response was defined by a complete closure of all external openings with no discharge on pressure. A complete radiological response (MRI), evaluated at least after six months of follow-up, was defined by a completely fibrotic sequela without abscess. A deep remission was defined as the association of a complete clinical response with a complete radiological response. RESULTS: A total of 43 patients were included (M/F: 22/21, median age 37 [26-45] years). The fistulas were already drained with seton(s) and were on biologic treatment. After a median follow-up of 383 (359-505) days, 28 (65%) patients showed a clinical response (22 complete and 6 partial) and 16 (37%) achieved a deep remission. The Perineal Disease Activity Index decreased significantly after treatment: 39 (91%) patients reported symptomatic improvement in terms of discharge, pain, and induration, and 28 (65%) no longer had any perineal symptoms. No severe adverse events were reported. A short history of Crohn's disease <3 years was significantly associated with deep remission (OD 4.5 [1.0-19.1], p = 0.04). CONCLUSION: Darvadstrocel injection resulted in a clinical response for two thirds of patients and deep remission for one third. A shorter duration of Crohn's disease was associated with deep remission.

[Anal fistulas: Sparing the sphincter]. / Fistules anales, épargner le sphincter.

ANAL FISTULAS: SPARING THE SPHINCTER. Fistulotomy is the most used treatment for anal fistula. It is very effective with a cure rate of over 95% but carries a risk of incontinence. This has led to the development of various sphincter sparing techniques. The injection of biological glue or paste and the insertion of a plug have disappointing results and are expensive. The rectal advancement flap is still practised because of its cure rate of around 75% but it may result in some incontinence. Intersphincteric ligation of the fistula track and laser treatment are widely practised in France with cure rates between 60 and 70%. Video-assisted anal fistula treatment as well as injections of adipose tissue, stromal vascular fraction, platelet-enriched plasma and/or mesenchymal stem cells are emerging techniques for which even better results are expected.

FISTULES ANALES, ÉPARGNER LE SPHINCTER. La fistulotomie est le traitement le plus souvent utilisé dans la fistule anale. Elle est très efficace, avec un taux de guérison supérieur à 95 %, mais expose à un risque d'incontinence. Cela a conduit au développement de diverses techniques d'épargne sphinctérienne. L'injection de colle ou de pâte biologique ainsi que la mise en place d'un plug ont des résultats finalement décevants et un coût élevé. Le lambeau rectal d'avancement est encore pratiqué en raison de son taux de guérison aux alentours de 75 %, mais il peut se solder par quelques troubles séquellaires de la continence. La ligature intersphinctérienne du trajet fistuleux et le laser sont largement pratiqués en France, avec des taux de guérison oscillant entre 60 et 70 %. Le traitement vidéo-assisté du trajet fistuleux ainsi que les injections périfistuleuses de tissu adipeux, de fraction vasculaire stromale, de plasma enrichi en plaquettes et/ou de cellules souches mésenchymateuses sont des techniques émergentes dont on espère de meilleurs résultats encore.

Complications of Mesh Sacrocolpopexy and Rectopexy: Imaging Review.

Sacrocolpopexy and rectopexy are commonly used surgical options for treatment of patients with pelvic organ and rectal prolapse, respectively. These procedures involve surgical fixation of the vaginal vault or the rectum to the sacral promontory with mesh material and can be performed independently of each other or in a combined fashion and by using an open abdominal approach or laparoscopy with or without robotic assistance. Radiologists can be particularly helpful in cases where patients' surgical histories are unclear by identifying normal sacrocolpopexy or rectopexy mesh material and any associated complications. Acute complications such as bleeding or urinary tract injury or stricture are generally evaluated with CT. More chronic complications such as mesh extrusion or exposure with or without fistulization to surrounding structures are generally evaluated with MRI. Other complications can have a variable time of onset after surgery. Patients with suspected bowel obstruction are generally evaluated with CT. Those with suspected infection, abscess formation, and discitis or osteomyelitis may be evaluated with MRI, although CT evaluation may be appropriate in certain scenarios. The authors review the sacrocolpopexy and rectopexy surgical techniques, discuss appropriate imaging protocols for evaluation of patients with suspected complications, and illustrate the normal appearance and common complications of these procedures. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.

[The rôle of MRI in exploration anorectal pathologies]. / Place de l'IRM pour explorer les pathologies anorectales.

PLACE DE L'IRM POUR EXPLORER LES PATHOLOGIES ANORECTALES. L'imagerie par résonance magnétique (IRM) est l'un des examens d'imagerie les plus utiles à l'exploration des pathologies ano rectales. Elle est complémentaire de l'examen clinique et de l'endo scopie. Elle permet de fournir des données indispensables à une prise en charge optimale du patient par le proctologue, le chirurgien ou l'oncologue en fonction de la nature de l'atteinte anale ou rectale. Il est nécessaire de respecter les différentes indications de cet examen, qui ont été bien définies pour chaque pathologie par les différentes sociétés savantes. Le protocole de l'IRM varie en fonction de la zone explorée et de la pathologie suspectée. C'est pourquoi il est indispensable de fournir au radiologue les informations nécessaires telles que la suspicion diagnostique, les données cliniques, ainsi que les résultats des examens complémentaires déjà réalisés. Les indications les plus fréquentes de l'IRM en proctologie sont les tumeurs anales et rectales. L'IRM permet le bilan initial de l'extension locorégionale de la tumeur ainsi que le suivi oncologique précoce et tardif grâce à l'étude comparative des examens de surveillance par rapport au bilan initial. L'IRM est indispensable pour l'exploration des suppurations anopérinéales complexes, en particulier liées à la maladie de Crohn. Elle permet la réalisation du bilan lésionnel initial ainsi que le contrôle post-drainage. En cas de suspicion de maladie de Verneuil ou de sinus pilonidal infecté, l'IRM participe à l'orientation vers le diagnostic étiologique. La déféco-IRM est une variante particulière de l'IRM pelvienne et périnéale. Elle fait partie du bilan des dysfonctions du plancher pelvien, car elle permet l'étude du comportement des différents organes pelviens au cours des efforts de poussée et de défécation. Les fissures anales et les thromboses hémorroïdaires sont les causes les plus fréquentes de douleurs anales. Leur diagnostic est purement clinique. En cas d'examen proctologique normal, l'IRM sert à chercher une autre cause à ces douleurs.

THE ROLE OF MRI IN EXPLORATION ANORECTAL PATHOLOGIES. Magnetic resonance imaging (MRI) is one of the most useful imaging modalities for the exploration of anorectal pathologies. It is complementary to the clinical examination and endoscopy. It provides essential elements for optimal care of the patient by the proctologist, the surgeon or the oncologist depending on the nature of the anal or rectal condition. It is necessary to respect the different indications of this exam which have been well defined for each pathology by the different scientific societies. The MRI protocol varies depending on the site to be investigated and the pathology suspected. Therefore, it is essential to provide the radiologist with the necessary information such as the diagnostic suspicion, clinical findings, and the results of previous paraclinical examinations. MRI ensures the initial assessment of the locoregional extension of the tumor as well as the early and late oncological follow-up thanks to the comparative study of the surveillance examinations with the initial exam. MRI is essential for the assessment of complex anoperineal suppurations, in particular those related to Crohn's disease. It is necessary for the initial lesional assessment and for the post-drainage control. In case of suspicion of Verneuil's (hidradenitis suppurativa) disease or infected pilonidal sinus, MRI helps to orientate towards the right etiological diagnosis. MR defecating proctography is a particular variant of pelvic and perineal MRI. It is performed as part of the assessment of pelvic floor dysfunctions because it allows the study of the dynamics of the different pelvic organs during straining and defecation. Anal fissures and hemorrhoidal thrombosis are the most frequent etiologies of anal pain. Their diagnosis is purely clinical. If the proctological examination is normal, MRI is used to search for other causes of anal pain.

Integrated TOPSIS-COV approach for selecting a sustainable PET waste management technology: A case study in Qatar.

In 2018, the global annual consumption of Polyethylene terephthalate (PET) bottles was approximately 27.64 million tons, with one million bottles sold worldwide every minute. Unmanaged PET bottles in the environment lead to a series of negative effects on the health of humans and ecosystems. Therefore, the objective of this research was to evaluate the sustainability of eight different PET waste bottle treatment methods using a holistic multi-criteria decision-making approach that combined the technique for order of preference by similarity to ideal solution (TOPSIS) with analytic hierarchy (AHP; TOPSIS-AHP) and coefficient of variation (COV; TOPSIS-COV) approaches. To the best of our knowledge, TOPSIS-COV has not yet been used for waste management. The treatment methods were compared and analyzed against twelve different performance criteria representing three pillars of sustainability: environmental, economic, and social. Both approaches determined closed-loop recycling to be optimal for treating PET waste bottles. The weights of performance indicators obtained using the COV and AHP approaches were comparable, except for cost, photochemical oxidant potential, and human toxicity. The large dispersion in the values of the photochemical oxidant potential causes it to have a higher weight in the COV approach. For cost, the weight was higher using the AHP approach by approximately 12%, which reflects the preference of decision-makers to reduce costs of ventures.

Synthesis and preparation of acid capped CdSe nanocrystals as successful adsorbent and photocatalyst for the removal of dyes from water and its statistical physics analysis.

In this study, mercaptosuccinic acid capped CdSe nanocrystals were successfully synthesized and used as photocatalyst for the effective removal of methylene blue (MB) inaqueous solution under visible light and sunlight irradiations including its analysis with statistical physics theory. Dye adsorption properties of these nanocrystals were investigated via experimental kinetics and equilibrium studies. These experimental data were modeled via the application of statistical physics theory to explain the corresponding adsorption mechanism and to characterize the steric and energetic parameters involved in the dye removal. A maximum adsorption capacity of 27.07 mg g-1 (80% of dye removal) was observed in 10 min using an initial concentration of 30 mg L-1. Statistical physics calculations indicated that the adsorption energy was lower than 40 kJ mol-1. It was also established that the dye adsorption was associated to the electrostatic interactions and hydrogen bonding where dye aggregation and multi-molecular adsorption were expected. Overall, the dye removal was a spontaneous, feasible and exothermic. It was concluded that adsorption properties of CdSe-MSA nanocrystals improved the dye photo-catalytic degradation efficiency under visible light thus achieving up to 80% degradation efficiency in 60 min. The synergic effect of adsorption and photo-catalytic degradation performance was mainly due to the surface area (136.43 m2 g-1), small size (3.7 nm), and structural defects (selenium vacancies Se, interstitial of cadmium ICd) of CdSe nanocrystals, which enhanced both the response of these nanomaterials to visible light and their photo-catalytic activity. In summary, these nanocrystals are promising materials to be used in wastewater treatment under sunlight for the removal of organic compounds like dyes.

Fractal analysis improves tumour size measurement on computed tomography in pancreatic ductal adenocarcinoma: comparison with gross pathology and multi-parametric MRI.

OBJECTIVES: Tumour size measurement is pivotal for staging and stratifying patients with pancreatic ductal adenocarcinoma (PDA). However, computed tomography (CT) frequently underestimates tumour size due to insufficient depiction of the tumour rim. CT-derived fractal dimension (FD) maps might help to visualise perfusion chaos, thus allowing more realistic size measurement. METHODS: In 46 patients with histology-proven PDA, we compared tumour size measurements in routine multiphasic CT scans, CT-derived FD maps, multi-parametric magnetic resonance imaging (mpMRI), and, where available, gross pathology of resected specimens. Gross pathology was available as reference for diameter measurement in a discovery cohort of 10 patients. The remaining 36 patients constituted a separate validation cohort with mpMRI as reference for diameter and volume. RESULTS: Median RECIST diameter of all included tumours was 40 mm (range: 18-82 mm). In the discovery cohort, we found significant (p = 0.03) underestimation of tumour diameter on CT compared with gross pathology (Δdiameter3D = -5.7 mm), while realistic diameter measurements were obtained from FD maps (Δdiameter3D = 0.6 mm) and mpMRI (Δdiameter3D = -0.9 mm), with excellent correlation between the two (R2 = 0.88). In the validation cohort, CT also systematically underestimated tumour size in comparison to mpMRI (Δdiameter3D = -10.6 mm, Δvolume = -10.2 mL), especially in larger tumours. In contrast, FD map measurements agreed excellently with mpMRI (Δdiameter3D = +1.5 mm, Δvolume = -0.6 mL). Quantitative perfusion chaos was significantly (p = 0.001) higher in the tumour rim (FDrim = 4.43) compared to the core (FDcore = 4.37) and remote pancreas (FDpancreas = 4.28). CONCLUSIONS: In PDA, fractal analysis visualises perfusion chaos in the tumour rim and improves size measurement on CT in comparison to gross pathology and mpMRI, thus compensating for size underestimation from routine CT. KEY POINTS: • CT-based measurement of tumour size in pancreatic adenocarcinoma systematically underestimates both tumour diameter (Δdiameter = -10.6 mm) and volume (Δvolume = -10.2 mL), especially in larger tumours. • Fractal analysis provides maps of the fractal dimension (FD), which enable a more reliable and size-independent measurement using gross pathology or multi-parametric MRI as reference standards. • FD quantifies perfusion chaos-the underlying pathophysiological principle-and can separate the more chaotic tumour rim from the tumour core and adjacent non-tumourous pancreas tissue.

Fast and effective catalytic degradation of an organic dye by eco-friendly capped ZnS and Mn-doped ZnS nanocrystals.

Undoped and manganese doped ZnS nanocrystals encapsulated with thioglycolic acid (ZnS-TGA) were synthesized and characterized with different techniques, and finally tested in the photodegradation of a methyl orange in aqueous solution under UV and sunlight irradiations. FTIR and X-ray diffraction results confirmed the functionalization of these nanocrystal surface by thioglycolic acid and the formation of crystalline structures of ZnS and Mn-doped ZnS with cubic and hexagonal phases. Calculated average size of ZnS nanocrystals was in the range of 2-3 nm. It was observed a blue shift of the absorbance threshold and the estimated bandgap energies were higher than that of Bulk ZnS thus confirming the quantum confinement effect of charge carriers. Photoluminescence spectra of ZnS nanocrystals exhibited emission in the range of 410-490 nm and the appearance of an additional emission band around 580 nm (2.13 eV) connected to the 4T1 → 6A1 transition of the Mn2+ions. Photodegradation of methylene orange with undoped and Mn-doped ZnS-TGA nanocrystals was investigated. Dye adsorption prior to photocatalysis using nanocrystals was studied via kinetic and equilibrium experiments. The maximum dye adsorption capacity on doped ZnS-TGA was ~ 26.98 mg/g. The adsorption kinetic was found to follow the pseudo-second-order kinetic model. A statistical physics model was used to analyze the equilibrium data where the calculated adsorption energy was 17-18 kJ/mol. It was concluded that the dye adsorption was associated to the hydrogen interaction where the removal process was feasible and multi-molecular at 25 °C. The photocatalytic activity of undoped ZnS nanoparticles under UV irradiation showed better efficiency than doped nanocrystals thus indicating that manganese doping generated a dropping of the photocatalytic degradation of the dye. Dye degradation efficiency of 81.37% using ZnS-TGA nanocrystals was achieved after 6 min, which indicated that ZnMnS-TGA nanocrystals may be considered an alternative low cost and environmental friendly material for facing water pollution caused by organic compounds via photodegradation processes.

A particle swarm optimization approach for predicting the number of COVID-19 deaths.

The rapid spread of the COVID-19 pandemic has raised huge concerns about the prospect of a major health disaster that would result in a huge number of deaths. This anxiety was largely fueled by the fact that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for the disease, was so far unknown, and therefore an accurate prediction of the number of deaths was particularly difficult. However, this prediction is of the utmost importance for public health authorities to make the most reliable decisions and establish the necessary precautions to protect people's lives. In this paper, we present an approach for predicting the number of deaths from COVID-19. This approach requires modeling the number of infected cases using a generalized logistic function and using this function for inferring the number of deaths. An estimate of the parameters of the proposed model is obtained using a Particle Swarm Optimization algorithm (PSO) that requires iteratively solving a quadratic programming problem. In addition to the total number of deaths and number of infected cases, the model enables the estimation of the infection fatality rate (IFR). Furthermore, using some mild assumptions, we derive estimates of the number of active cases. The proposed approach was empirically assessed on official data provided by the State of Qatar. The results of our computational study show a good accuracy of the predicted number of deaths.

Data of the design of solar assisted district cooling systems.

The collected datasets are relevant and related to Optimization of Design and Operation of Solar Assisted District Cooling Systems [1] paper. Part of the data is collected on the main and common components of the system. That includes solar collectors unit price ($/m2), type, and efficiency; absorption chiller capacity (kW), type, initial cost ($), and COP; the hot/chilled water thermal energy storage tank type, initial cost ($) and capacity (kWh); and auxiliary boiler initial cost ($), capacity (kW), type and efficiency. The other part of the data is collected on hourly cooling demand over the year for the state of Qatar (kW), hourly global solar irradiance over the year for the state of Qatar (W/m2) and variable cost of producing and storing chilled and hot water ($/kWh, $/kW). The data are collected from different resources such as government websites, commercial websites, government sectors, journals and real-life case studies. The value of this data comes from that most of the data required to conduct such research in this area are available in one resource. Also, some of the data such as the annual hourly cooling demand and global solar radiation are not available online. Moreover, the collected data are already filtered and the units are consistent and ready to be used. Finally, the data considered to be crucial and the core of such research are available in this paper.

Physical properties and conductivity relaxation processes in sodium sulfo-borophosphate glasses.

Many physical properties of a sodium-borophosphate glass system (BPSx) having the starting composition (30H3BO3 + xNa2SO4 + (60 - 2x) NaH2PO4 + 10ZnO) were detremined. It was found that the glass density ρ, the transition temperature T g, and the optical gap energy decrease whereas the molar volume and Urbach ▵E energy increases with the substitution of Na2O by Na2SO4. The analysis of the evolution of the complex dielectric permittivity ε * and the complex electric modulus M * with temperature and composition of the glass indicates that the dielectric loss is dominated by ionic conduction, and the relaxation processes are non-Debye type. The evolution of the Kohlrausch-Williams-Watts (KWW) exponent ß, estimated from the imaginary part of the electric modulus indicates that the investigated glass behaves as an intermediate elastic system as compared to flexible and stressed rigid phase. The obtained values of the decoupling index are of the same order of magnitude as observed for fast-ion conducting glasses. From the analysis of the experimental data, we may suggest that the glass sample BPS4 is the more thermally stable and has the highest ionic conductivity since it has the highest dielectric constant favorable for the dissociation of sodium salt.

Use of MPA-capped CdS quantum dots for sensitive detection and quantification of Co2+ ions in aqueous solution.

Water soluble CdS quantum dots (QDs) were synthesized by a simple aqueous chemical route using mercaptopropionic acid (MPA) as a stabilizer. These QDs had a fluorescence emission band maximum at 540 nm with a FWHM ∼130 nm and a quantum yield of ∼12%. Transmission electronic microscopy images were used to determine the QD diameter of 8.9 ±â€¯0.4 nm. From this value we calculated the molecular mass M(QD) = 1.17 × 106 g mol-1 and the extinction coefficient at the band edge (450 nm) ε450 = 4.7 × 106 cm-1 M-1, which allowed to determine the true molar concentration of 17 nM for spectroscopic measurements in solution. The fluorescence intensity of MPA-CdS QDs was quenched only in the presence of Co2+ ions, but not in the presence of thirteen other metal cations. The fluorescence quenching of MPA-CdS QDs appeared proportional to the Co2+ concentration in the range 0.04-2 µM. Based on a fluorescence peak position and a lifetime both independent from Co2+ concentration, the quenching mechanism of MPA-CdS QDs appeared static. Because the strong electronic absorption of Co2+ overlaps the emission of QDs, our results can be explained by Förster energy transfer from QD to the bound Co2+ cations.