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Objective: This study aimed to develop a stable and scalable enteric film-coated tablet for the gastric irritant dexibuprofen. Methods: Utilizing direct compression with super-disintegration (crospovidone), the optimal core batches were coated with Opadry white seal coat and enterically coated with Eudragit®L100 with pigment (Talc), demonstrating a 12% weight increase; release and integrity were assessed using specific pH buffers and SEM, with stability testing confirming a six-month shelf life at 40 °C and 75% RH. Results: The optimized formulation achieved 99.87% release in phosphate buffer within 60 min, maintained integrity for 120 min in acidic conditions, and exhibited superior bioavailability compared to Innovifen with relative bioavailability ≈of 121% and elevated Cmax (18.35 µg/ml compared to 11.1 µg/ml). Conclusion: These results highlight the potential of this formulation to enhance patient safety and efficacy through delayed enteric technology and fast intestinal release. [ABSTRACT FROM AUTHOR]

In this paper, the surface morphology of the parts was improved by the in‐mold decoration and microcellular foaming injection molding (MIM‐IMD), and the mechanical properties of the parts were improved by inorganic particles modification. The effects of different inorganic particles (CaCO3, MMT, Talc) on the rheological behavior, crystallization properties, cell structure, surface quality, and mechanical properties of the MIM‐IMD composites were analyzed through experimental research and comprehensive macro and micro characterization. It was found that the foamed composite added with MMT had the highest surface quality, the best cell structure, the minimum average cell diameter of 78.4 μm and the maximum cell density of 3.09 × 106 cells/cm3. Talc improved the crystallinity of polypropylene (PP) matrix, and the resulting mechanical properties were the most significant improvement. Tensile, flexural, and impact strength were increased by 20.3%, 11.6%, and 45.2%, respectively. Highlights: The MIM‐IMD process was used to improve the surface quality of the samples.The enhancement of different inorganic particles on the properties were compared.The properties were evaluated by macro‐ and micro‐characterization.Inorganic particles can significantly improve the cell structure.Inorganic particles can greatly improve mechanical properties. [ABSTRACT FROM AUTHOR]

As a distinguished luminescent matrix, rare earth (RE)-doped glass has garnered considerable attention across lighting, display, laser, and related domains. Nonetheless, the limited luminescent efficiency of such glass imposes constraints on its extensive utilization. In addressing this challenge, we have developed a novel formulation involving heavily Eu3+-doped black talc glass, boasting exceptional optical characteristics. Structural examination has validated the successful synthesis of the parent glass matrix comprising [SiO 4 ] and [AlO 4 ] units. With the escalating of Eu3+ doping concentrations, the glass manifested an upward trend in both density and refractive index. Under the excitation of 393 nm light, the glass exhibited strong red light emission, demonstrating a high internal quantum efficiency (IQE) of up to 84.67 %, surpassing markedly other Eu3+-doped glass variants. Furthermore, even under elevated temperatures reaching 150 °C, the glass retained 86.2 % of its luminescent intensity at room temperature, indicative of superior thermal resilience vis-à-vis alternative glass systems. As a proof-of-concept, we encapsulated a white light-emitting diode (W-LED) assembly employing a 395 nm LED chip, Eu3+-doped glass, BaMgAl 10 O 17 :Eu2+ blue phosphor, and Ba 2 SiO 4 :Eu2+ green phosphor. The resultant device exhibited favorable chromaticity coordinates (0.3566, 0.3994), boasting a correlated color temperature (CCT) of 4791K and a high color rendering index (CRI) of 91. In summary, this investigation employs black talc ore to synthesize luminescent glass, thereby not only diversifying the application scope of black talc but also augmenting its additional value, while notably enhancing the luminescent efficiency of the glass through heavy Eu3+ doping. Through empirical validation, the significant potential benefits of Eu3+-doped black talc glass in the realm of W-LED lighting were convincingly demonstrated. [ABSTRACT FROM AUTHOR]

The influence of talc microparticles on metabolism and morphology of S. rimosus at various initial organic nitrogen concentrations was investigated. The shake flask cultivations were conducted in the media with yeast extract (nitrogen source) concentration equal to 1 g YE L− 1 and 20 g YE L− 1. Two talc microparticle concentrations of 5 g TALC L− 1 and 10 g TALC L− 1 were tested in microparticle-enhanced cultivation (MPEC) runs. A high nitrogen concentration of 20 g YE L− 1 promoted the development of small agglomerates (pellets) of projected area lower than 105 µm2 and dispersed pseudohyphae. A low nitrogen concentration of 1 g YE L− 1 led to the limitation of S. rimosus growth and, in consequence, the development of the smaller number of large pseudohyphal agglomerates (pellets) of projected area higher than 105 µm2 compared to the culture containing a high amount of nitrogen source. In both cases talc microparticles were embedded into pellets and caused the decrease in their sizes. The lower amount of talc (5 g TALC L− 1) usually caused the weaker effect on S. rimosus morphology and metabolite production than the higher one. This correlation between the microparticles effect on morphology and metabolism of S. rimosus was especially noticeable in the biosynthesis of oxytetracycline, 2-acetyl-2-dicarboxamide oxytetracycline (ADOTC) and spinoxazine A. Compared to the control run, in MPEC their levels increased 4-fold, 5-fold and 1.6-fold respectively. The addition of talc also improved the production of 2-methylthio-cis-zeatin, lorneic acid J and milbemycin A3. [ABSTRACT FROM AUTHOR]

Introduction: Medical thoracoscopy is a minimally invasive and safe procedure mostly performed for unexplained exudative pleural effusions but may be considered for pneumothorax (PNX). Methods: This retrospective study included participants affected by PNX who underwent medical thoracoscopy with talc poudrage at a single academic hospital from 2008 to 2021. The primary endpoint was the observation of complete radiographical lung re-expansion and absence of air supply from the chest drain within 7 days of medical thoracoscopy. The secondary endpoint was achieving no recurrence of ipsilateral PNX at 24 months post-discharge. Results: A total of 95 patients affected by primary spontaneous PNX (PSP), secondary spontaneous PNX (SSP), iatrogenic, and traumatic PNX were enrolled. An additional procedure was required by 17.89% of patients, and only one patient with SSP required subsequent surgery. Recurrence of PNX occurred on the same side within 24 months after discharge in 9.47% of patients, with a median time to recurrence of 13.5 months. The PSP group was significantly more likely to achieve the primary endpoint. Pleural morphology was significantly associated with reaching the primary endpoint, while receiving a cumulative dose of talc greater than or equal to 4 g during hospitalization was associated with a lower risk of meeting it. Receiving a cumulative dose of talc greater than or equal to 4 g led in all cases to the achievement of the secondary endpoint. Patients with iatrogenic and traumatic PNX had an excellent prognosis in both the short- and long-term evaluation. Conclusion: Medical thoracoscopy is an effective procedure for treating PNX in the acute setting in selected cases while preventing long-term relapses. Large prospective clinical studies are needed to support and better define the role of medical thoracoscopy in current clinical practice. [ABSTRACT FROM AUTHOR]

In the iron ore mines of Gol-Gohar, talc presents along with magnetite mineral, which goes to waste thickeners after recovery of magnetite. Considering that talc constitutes more than 20% of waste, it can be sold as a by-product with a high added value, if it is recovered and purified. In this study, the extraction of talc from the tailings of the Gol-Gohar complex has been investigated. Sampling was done from the central thickener underflow, which contained 65% of dust factory tailings and 35% of concentrate factory tailings. Based on characteristic studies, the tailings from the central thickener had about 23% talc. Flotation tests were performed using different chemicals, such as pine oil and polypropylene glycol as frothers, oleic acid as collector, Armac C and Armac T, and pH 7 and 11. In the best condition, pH=11, polypropylene glycol as a frother, and not using a collector, a talc concentrate with a purity of more than 95%, a weight recovery of 10.4%, and a talc recovery of 42% was produced. Also, flotation kinetic tests were performed under optimal conditions, and it was shown that most of the first-order kinetic models and the second- order kinetic model excellently match the talc flotation recovery over the time [ABSTRACT FROM AUTHOR]

Abstract Introduction Medical thoracoscopy is a minimally invasive and safe procedure mostly performed for unexplained exudative pleural effusions but may be considered for pneumothorax (PNX). Methods This retrospective study included participants affected by PNX who underwent medical thoracoscopy with talc poudrage at a single academic hospital from 2008 to 2021. The primary endpoint was the observation of complete radiographical lung re-expansion and absence of air supply from the chest drain within 7 days of medical thoracoscopy. The secondary endpoint was achieving no recurrence of ipsilateral PNX at 24 months post-discharge. Results A total of 95 patients affected by primary spontaneous PNX (PSP), secondary spontaneous PNX (SSP), iatrogenic, and traumatic PNX were enrolled. An additional procedure was required by 17.89% of patients, and only one patient with SSP required subsequent surgery. Recurrence of PNX occurred on the same side within 24 months after discharge in 9.47% of patients, with a median time to recurrence of 13.5 months. The PSP group was significantly more likely to achieve the primary endpoint. Pleural morphology was significantly associated with reaching the primary endpoint, while receiving a cumulative dose of talc greater than or equal to 4 g during hospitalization was associated with a lower risk of meeting it. Receiving a cumulative dose of talc greater than or equal to 4 g led in all cases to the achievement of the secondary endpoint. Patients with iatrogenic and traumatic PNX had an excellent prognosis in both the short- and long-term evaluation. Conclusion Medical thoracoscopy is an effective procedure for treating PNX in the acute setting in selected cases while preventing long-term relapses. Large prospective clinical studies are needed to support and better define the role of medical thoracoscopy in current clinical practice.

This is an article in the field of mineral processing engineering. Molybdenum has many good physical and chemical properties and is widely used in many fields. Molybdenum is mainly derived from molybdenite, but the resources of the easily beneficiated molybdenum ore have been gradually reduced after long-term development. Nowadays, talc-type and other refractory molybdenum ores have gradually become the focus of research. The separation of talc and molybdenite is a difficult point in the separation of talc-type molybdenum ores. The two has similar surface structures and natural floatability, and the separation is very difficult. This article summarizes the current research progress of talc-type molybdenum ore beneficiation technology and reagents, and proposes to strengthen the research and development of selective grinding of talc-type molybdenum ores and organic macromolecular reagents, and deepen the mechanism and effect of reagents and mineral surfaces. The study of the raw ore technological mineralogy is an important direction for sorting the talc-type molybdenum ore in the future.

RTV 10A silicone rubber composites have many applications in forming many medical products and one of the recent applications is for orthotic insoles. This is because the RTV silicon rubber has excellent flexibility, elasticity, and resistance against splitting. However, these mechanical properties still need improvement when applied in certain medical applications. One way to improve mechanical properties is by adding talc. The process of mixing silicon rubber with talc requires special techniques to prevent the formation of porosity that may lead to unexpected mechanical properties. This porosity occurs due to trapped air during the mixing process or pouring into molds. Efforts to eliminate this porosity include Vacuum Die Casting (VDC) techniques. This study presents the mechanical properties improvement of RTV 10A silicon rubber composite with the addition of using 30% talc. The objective is to achieve a more convenient orthotic insole to reduce the pain in human foot joints during walking due to planar stress. This study aims to reduce the porosity and minimize the trapped air by adding 30% talc into RTV 10A silicone rubber composite using VDC. In the experiment, the pressure variation was determined at -0.04 MPa, -0.06 MPa, -0.08 MPa, and -0.1 MPa through a mold size of 45 mm in diameter and thickness of 7 mm. Fluidity, density, porosity, and hardness were tested during the experiment. The results show that by decreasing vacuum pressure, the density and the hardness increase. This is because the size and distribution of porosity are decreased and more homogeny. Furthermore, it also produces higher fluidity. However, the porosity of the specimen after vacuum casting is not partially filled.

Sorption of Sr(II) and Eu(III) from aqueous solutions was studied using tin molybdate talc sorbent synthesized by the precipitation technique. The synthesized sorbent was characterized using different analytical tools, such as; FT-IR, SEM, XRD, XRF, TGA, and DTA. The sorption studies applied to Sr(II) and Eu(III) include the effects of shaking time, pH, concentrations, and saturation capacity. The sorption of Sr(II) and Eu(III) depends on pH, reaction kinetics obey the pseudo-2nd-order model, and the Langmuir model is better suited for the sorption isotherm. The thermodynamic parameters reflect an endothermic and spontaneous sorption process. Desorption studies showed that 0.1 M HCl was the best desorbing agent for the complete recovery of Sr(II) (96.8%) and Eu(III) (92.9%). Finally, the obtained data illustrates that the synthesized sorbent can be applied and used as an efficient sorbent for the sorption of Sr(II) and Eu(III) from aqueous solutions and can be used as a promising sorbent to remove Sr(II) and Eu(III). [ABSTRACT FROM AUTHOR]

Talc is a gangue mineral of most platinum group metals and base metal ores commonly found in the Southern African mineral repository. It is naturally hydrophobic, and invariably, the depression of talc is paramount and challenging in the flotation of these ores. This paper introduced alkaline gelatinised cassia tora gum (CTG) and locust bean gum (LBG) as novel talc depressants. The adsorption densities, thermochemical properties, and talc depression of these depressants were studied using adsorption, zeta potential and microflotation studies. Talc flotability in the absence of the depressant was 89%, which implied that the talc used in this study was naturally floatable. Adsorption studies revealed that CTG yielded the highest talc adsorption density, followed by LBG and carboxymethyl cellulose (CMC), and their adsorption densities were 5.8 mg/m2, 4.6 mg/m2 and 3.5 mg/m2, respectively. PGM flotation occurs at pH 9. Therefore, the zeta potential results at this pH were given more attention in the present study. The zeta potentials at pH 9 were −5.75 mV for LBG and CTG and −15 mV for CMC. In addition, the percentage of talc depression achieved in the microflotation studies decreased in the order of LBG > CTG > CMC; their respective values were 72% > 56% > 51%. Therefore, the zeta potential values agree with the adsorption and microflotation results observed in this study, i.e. LBG and CTG depressed talc more effectively than CMC. Finally, bench flotation results revealed that LBG had the greatest effect on talc depression at 100 g/t; while, CTG had the greatest effect on talc depression at 25 g/t. Thus, these results agreed with thermodynamic theory, viz. a low molecular weight polymer is effective at low dosages where the surface is unsaturated. In contrast, a high molecular weight polymer is effective at high dosages because there is enough quantity to cover the surface adequately. [ABSTRACT FROM AUTHOR]

Jointpoint Regression Software from the National Cancer Institute was used to model age-adjusted male and female pleural and peritoneal mesothelioma rates in the surveillance, epidemiology, and end results (SEER) 8, SEER 12, and SEER 22 cancer registries. Linear mixed models were then used to determine if there was a statistical association between U.S. cosmetic talc consumption and the 30-year lagged age-adjusted mesothelioma rates (1) over the reporting period for each registry and (2) for the periods of time identified by the jointpoint model where changes in the rate of mesothelioma occurred. Regardless of the SEER registry used, from the early-1980s through 2020, rates of peritoneal mesothelioma have remained steady or declined. Female pleural mesothelioma rates were unchanged from the early-1980s until 2017 when rates declined, while male rates peaked in the early 1990s and have since declined. Cosmetic talc consumption was not statistically associated with an increased rate of pleural or peritoneal mesothelioma in males or females, suggesting that the use of cosmetic talc products is not associated with the development of mesothelioma. [ABSTRACT FROM AUTHOR]

It has long been recognized that amphibole minerals, such as cleavage fragments of tremolite and anthophyllite, may exist in some talc deposits. We reviewed the current state of the science regarding the factors influencing mesotheliogenic potency of cleavage fragments, with emphasis on those that may co-occur in talc deposits, including dimensional and structural characteristics, animal toxicology, and the most well-studied cohort exposed to talc-associated cleavage fragments. Based on our review, multiple lines of scientific evidence demonstrate that inhaled cleavage fragments associated with talc do not pose a mesothelioma hazard. [ABSTRACT FROM AUTHOR]

Over the past several decades, there have been many epidemiology studies on talc and cancer published in the scientific literature, and several reviews and meta-analyses of talc and respiratory, female reproductive, and stomach cancers, specifically. To help provide a resource for the evaluation of talc as a potential human carcinogen, we applied a consistent set of examination methods and criteria for all epidemiology studies that examined the association between talc exposure (by various routes) and cancers (of various types). We identified 30 cohort, 35 case-control, and 12 pooled studies that evaluated occupational, medicinal, and personal-care product talc exposure and cancers of the respiratory system, the female reproductive tract, the gastrointestinal tract, the urinary system, the lymphohematopoietic system, the prostate, male genital organs, and the central nervous system, as well as skin, eye, bone, connective tissue, peritoneal, and breast cancers. We tabulated study characteristics, quality, and results in a systematic manner, and evaluated all cancer types for which studies of at least three unique populations were available in a narrative review. We focused on study quality aspects most likely to impact the interpretation of results. We found that only one study, of medicinal talc use, evaluated direct exposure measurements for any individuals, though some used semi-quantitative exposure metrics, and few studies adequately assessed potential confounders. The only consistent associations were with ovarian cancer in case-control studies and these associations were likely impacted by recall and potentially other biases. This systematic review indicates that epidemiology studies do not support a causal association between occupational, medicinal, or personal talc exposure and any cancer in humans. [ABSTRACT FROM AUTHOR]

The potential carcinogenicity of talc has been evaluated in many studies in humans and experimental animals published in the scientific literature over the last several decades, with a number of these studies reporting no associations between talc exposure and any type of cancer. In order to fully understand the current state of the science regarding the potential for talc to induce human cancers, we conducted a comprehensive and systematic review of the available experimental animal and mechanistic evidence (in conjunction with a systematic review of the epidemiology evidence in a companion analysis) to evaluate whether it supports talc as being carcinogenic to humans. We considered study quality and its impact on the interpretation of results and evaluated all types of cancer and all exposure routes. We also evaluated the evidence on the potential for talc to migrate in the body to potential tumor sites. We identified seven experimental animal carcinogenicity studies and 11 mechanistic studies of talc to systematically review. We found that several of the experimental animal carcinogenicity studies of talc have limitations that preclude their sensitivity to detect increases in tumor incidence. Regardless, the studies cover multiple exposure routes, species, and exposure durations, and none indicate that talc is a carcinogen in experimental animals except in rats under conditions of extremely high exposure that likely resulted in lung particle overload, a nonspecific effect of high exposures to poorly soluble particles, and not from any carcinogenic properties of talc. Lung particle overload leading to lung tumor formation has only been observed in rats and not in any other species, including humans. The mechanistic studies indicate that talc is not genotoxic or mutagenic, but can induce some effects that could be events on a possible pathway to carcinogenicity, mainly at high exposures or in in vitro studies with exposures of unclear relevance in vivo, but these effects are not consistent across studies and cell types. This systematic review of the experimental animal carcinogenicity and mechanistic evidence for talc indicates that an association between talc exposure and cancer is not expected in humans. Talc carcinogenicity is not plausible in any species except rats, and only when the exposure conditions are high enough to induce lung particle overload, which is not relevant to human exposures. [ABSTRACT FROM AUTHOR]

Librarians at a university had planned to check the collection prior to the library renovations that began in 2015. They had previous knowledge of the presence of a light greyish-white powder with an unpleasant odour (hereinafter referred to as 'powder') sprinkled between the pages of antiquarian books in the library archive. The purpose of this study was to identify this powder with the help of experts from both inside and outside the university. The powder was qualitatively analysed using gas chromatography with mass spectrometry after hexane extraction. The powder was examined under a polarised light microscope and a field-emission scanning electron microscope equipped with an energy-dispersive X-ray spectrometer. Benzene hexachloride (BHC) was detected in the powder. Talc was the most abundant particle in the powder. The powder also contained 0.52 wt% asbestos, which belonged to the tremolite-actinolite series. No other types of asbestos were detected. The powder was presumed to be a bulking agent for BHC, and its major constituent was talc. This is the first report on asbestos-containing insecticides. [ABSTRACT FROM AUTHOR]

The study was to improve the heat resistance of polylactic acid (PLA) through blending modification. Ethylene-methyl acrylate-glycidyl methacrylate (E-MA-GMA) and poly(butylene succinate) (PBS) and talc powder (talc) were added to PLA matric to prepare PLA/E-MA-GMA/PBS/talc blends. The effects of PLA/E-MA GMA/PBS/talc content on the mechanical properties, flowability, rheological properties, heat resistance of the blends were studied. The results show that with the change of PLA/EMAGMA/PBS/ talc blend system, the tensile strength of the blends gradually decreases, while the toughness and impact strength gradually increase, indicating the existence of partial toughening and compatibility between the blend materials. Theheat deflection temperature of the untreated blends remains relatively stable at around 55 °C, while the heat deflection temperature of the crystallized blends is generally higher than 90 °C. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is a widely used material with excellent properties. The mechanical strength, thermal stability, wettability, and anti-aging properties of PP can be further improved, especially for secondary recycled PP. Therefore, the study aimed to improve the properties of PP by waste PP and preparing talc-filled PP blends via a simple melt plasticization and re-cooling process. Through the addition of talc, hydrogen bonds were formed between the --OH groups in talc and the --CH3 groups on the PP carbon chain, resulting in a significant improvement in mechanical properties compared to virgin PP. The addition of 10% talc increased the fracture energy of the blends by nearly 142%. Therefore, the addition of talc in the secondary recycling of PP can effectively improve the performance of PP blends and enhance their sustainability in practical applications. [ABSTRACT FROM AUTHOR]

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RTV 10A silicone rubber composites have many applications in forming many medical products and one of the recent applications is for orthotic insoles. This is because the RTV silicon rubber has excellent flexibility, elasticity, and resistance against splitting. However, these mechanical properties still need improvement when applied in certain medical applications. One way to improve mechanical properties is by adding talc. The process of mixing silicon rubber with talc requires special techniques to prevent the formation of porosity that may lead to unexpected mechanical properties. This porosity occurs due to trapped air during the mixing process or pouring into molds. Efforts to eliminate this porosity include vacuum die casting (VDC) techniques. This study presents the mechanical properties improvement of RTV 10A silicon rubber composite with the addition of using 30% talc. The objective is to achieve a more convenient orthotic insole to reduce the pain in human foot joints during walking due to planar stress. This study aims to reduce the porosity and minimize the trapped air by adding 30% talc into RTV 10A silicone rubber composite using VDC. In the experiment, the pressure variation was determined at -0.04 MPa, -0.06 MPa, -0.08 MPa, and -0.1 MPa through a mold size of 45 mm in diameter and thickness of 7 mm. Fluidity, density, porosity, and hardness were tested during the experiment. The results show that by decreasing vacuum pressure, the density and the hardness increase. This is because the size and distribution of porosity are decreased and more homogeny. Furthermore, it also produces higher fluidity. However, the porosity of the specimen after vacuum casting is not partially filled. [ABSTRACT FROM AUTHOR]

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The link between talcum powder use and cancer, particularly ovarian cancer, has been a topic of scientific research and legal debate for several years. Studies have suggested a potential association between long-term talcum powder use in the genital area and an increased risk of ovarian cancer. The following report includes up-to-date evidence to support the potential link between talcum powder use and the risk of developing ovarian cancer. The International Agency for Research on Cancer, which is part of the World Health Organization, classified talc-based body powder as possibly carcinogenic to humans when used in the female genital area. However, other studies have not consistently supported this association, and thus more research is needed to establish a clear and definitive link between talcum powder use and cancer. Despite this, recent molecular-level data have linked talc to alterations in redox balance, gene mutations, and inflammatory responses. Specifically, we have identified a role for talc to induce the pro-oxidant state, inhibit apoptosis, and more importantly induced cellular transformation in normal ovarian cells. We presented unequivocal evidence to support our opinion that talc is not biologically inert and induces molecular changes that mimic the hallmarks of cancer. [ABSTRACT FROM AUTHOR]

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A multifunctional epoxy polymer wass used ass a chain extender for poly (butylene ssuccinate-co-terephthalate) (PBST), and the effects of chain extension condition on the propertiess of PBST/Talc (talcum powder) blendss were in-vesstigated during the melt-phasse reactive extrusion processss. The chain extender dossage, reaction temperature, and sscrew rotational sspeed were sstudied ass main factorss. The primary influence factors and their interactions were identified through an analyssiss of variance. The ressultss indicated that the influence of chain extender dossage iss mosst ssignificant, followed with a reaction temperature, whereass the influence of sscrew sspeed iss lessss. The melting and crysstallization temperaturess of PBST decreassed with an increasse in the chain extender dossage, and meanwhile its molecular weight, melt visscossity, and thermal sstability increassed. The modified PBST compounds* pressented an increasse in the breaking sitresis; but a decreasse in the breaking sstrain with an increasse in the chain extender dossage. Ressponsse ssurface analyssiss indicated that the optimal chain extenssion condition wass a chain extender dossage of 0. 66 %, a reaction temperature of 200 °C, and a sscrew sspeed of,300 r/min. [ABSTRACT FROM AUTHOR]

We present here a case of fibrotic hypersensitivity pneumonitis in a patient with a 7-year history of daily inhaled crystal methamphetamine abuse. The patient's history of chronic exertional dyspnea attributable to progressive methamphetamine abuse, family history and autoimmune features pointed to methamphetamine as the initiator of fibrotic hypersensitivity pneumonitis. After excluding other causes, the patient's clinical, laboratory, radiological and histopathological findings indicated that the fibrotic hypersensitivity pneumonitis had been induced by methamphetamine. [ABSTRACT FROM AUTHOR]

The thermal expansion coefficient of talc has been measured using a high-temperature thermal optical expansion apparatus over a temperature range of 296 to 1473 K. The results show a gradual increase in the thermal expansion coefficient between 296 and 1086 K, and a rapid and substantial increase between 1086 and 1316 K, but exhibit a decline trend between 1316 and 1473 K. At lower temperatures, changes in crystal structure are the primary mechanism governing thermal expansion; at higher temperatures, the dehydration phase transition and the resulting formation of cracks are the primary contributors to thermal expansion. The volume of talc exhibits a linear increase with temperature, described by the equation: . At high temperatures (573–1073 K), by fitting the expansion data to the Grüneisen thermal equation of state, bulk modulus K0​ = 47.3 ± 0.9 GPa, pressure derivative = 6.2 ± 0.4, cell volume V0​ = 904.5 ± 0.6 ų, and Debye temperature θ = 829.3 ± 0.6 K were obtained at 0 K. The presence of talc reduces the density of subduction zones, facilitating the exhumation of oceanic eclogites. [ABSTRACT FROM AUTHOR]

Ophiolite-derived clastic rocks of the Rassokha terrane in the Chersky Range of the Verkhoyansk−Kolyma folded area were studied to obtain representative characteristics of the eroded source metamorphosed ultramafic and mafic rocks, to gain an insight into the possible geodynamic setting in which the protoliths of these rocks were formed, and to identify the possible source of the eroded material. The composition of lithoclasts and detrital minerals of the serpentinite and listwanite sandstones suggests that their source was composed of serpentinite, chloritite, listwanite, and dolomite rocks and that this source was proximal. Prior to the source erosion, the ultramafic and mafic rocks were metamorphosed and recrystallized, listwanite was formed, and the ultramafic rocks were tectonically disintegrated and combined with units of carbonate rocks (dolomite). Ultramafic rocks from lithoclasts experienced allochemical metamorphic retrogression during at least the latest stage of their serpentinization in a nonoceanic setting, where also the listwanite was formed. The Late Neoproterozoic ophiolites of the collisional belt of the Chersky Range were the most probable source for the protoliths of the clastic material. The protoliths of the ophiolite rock were probably formed in a backarc setting. Considered together with the published ages, our data indicate that relics of suprasubduction oceanic lithosphere of the Neoproterozoic basin occurred in the Chersky Range. [ABSTRACT FROM AUTHOR]

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This study aims to assess the effectiveness of water-based formulations featuring m-2HEAOL and talc particles in deep drawing applications. The coefficient of friction (COF) was measured through bending under tension (BUT) tests, while the interaction mechanism between protic ionic liquid (PIL) and talc particles was analysed using FTIR, XPS, and TGA analyses. The results indicate that the formulation containing 8 wt% PIL and 0.5 wt% talc exhibited the best lubricating performance. This was due to the interaction of the PIL oleate molecules with the Mg found in the talc basal layer, which enhanced the cleavage capacity of this mineral, ultimately improving the lubricity of the formulation. [ABSTRACT FROM AUTHOR]

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Mapping a tourist's travel frequency and behaviour over time (as outlined in the Tourism Experience Life Cycle (TELC)), may be as important as Butler's Tourism Area Life Cycle (TALC) as there is a 'need to understand the life cycle for a tourist' (Dodds, 2020, p. 219). This paper, using a quantitative approach of 980 Canadians, tests the validity of the TELC model to determine if sustainable travel behaviours increase the more a tourist travels. Two hypothesis are tested in this paper. First, the more trips taken by a traveller, the more sustainable their behaviur will be and second, the more a traveller revisits the same destination, the more sustainable their travel behaviour will be. Findings, supported through ANOVA and hierarchical multi-step regression, show that there is a relationship between the number of trips taken and sustainable behaviour. The greater the number of domestic and/or international trips that a leisure traveller takes, the more likely their behaviour while travelling will be more sustainable. On the other hand, findings also outline that the more frequently a visitor returns to the same destination, the less likely they will practice sustainable travel behaviour. [ABSTRACT FROM AUTHOR]

Natural Mg phyllosilicates are potential sources of divalent cations, which are necessary for the mineralization of CO2 into carbonates. The influence of inorganic () and organic (oxalate and citrate) ligands on the dissolution kinetics of talc and serpentine was studied in experiments in a flow-through reactor at 25°C. The dissolution rates of natural silicates r (mol cm–2 s–1) in solutions of various composition were calculated at the stationary stage of dissolution after a rapid initial stage, which is characterized by the formation of a surface leached layer depleted in magnesium. The presence of ligands increases the dissolution rate of magnesium silicates due to the formation of surface complexes, which leads to magnesium separation from the surface and transfer into solution. The initial incongruent stage may be the most promising for the development of carbonation technologies, because the minimum removal of the network-forming elements prevents the undesirable formation of secondary minerals (for example, clays), which exclude divalent cations from the carbonation process and greatly reduce the permeability of rocks. [ABSTRACT FROM AUTHOR]

The ability to modulate direct expanded product structures improves the versatility and range of product applications. The effect of nucleating agents, namely, talc and calcium carbonate (CC), on the expansion characteristics of pea starch extrudates as impacted by screw speed was explored. Pea starch blends with increasing levels of nucleating agents (0.25%, 1%, and 2%) at 18% moisture (w.b.) were extruded across a range of screw speeds (150, 250, 350, and 450 rpm). The water absorption index, water solubility index (WSI), expansion ratio (ER), unit density, and cell count were determined to evaluate the performance of nucleating agents. The nucleating efficiency of CC, as assessed by cell count, improved with increasing screw speeds. In contrast, the nucleating efficiency of talc was influenced by inclusion levels irrespective of screw speed. ER values ranged from 2.10 to 2.88, where higher nucleating agent inclusions and screw speeds corresponded with lower ER values. Increased nucleating agents and screw speeds corresponded to higher WSI values suggesting the nucleating agents promoted starch degradation. The nucleating agents appeared to promote flow instabilities indicated upon assessment of the extrudate surface. Practical Application: This study provides helpful information on the expanded extrudate structure of pea starch as influenced by screw speed and nucleating agents. These findings may help the food industry select processing parameters and appropriate nucleating agent inclusion levels when producing new expanded products with unique textures. [ABSTRACT FROM AUTHOR]

The central tenet of the tourism-area lifecycle (TALC) rests on the idea of change. This paper utilized latent-growth curve modelling (LGCM) to synthesize a time-variant lifecycle model that quantifies changes in TALC-based hotel development. We accommodated the model with cross-lagged analysis to draw causal inferences. Based on data collected from 197 economies from UNWTO, findings reveal that the onset and growth rate of hotel development are associated with growth trajectories of tourist arrivals and overnight stays, which are subsequently associated with the growth trajectory of travel expenditure. A reciprocal influence between hotel development and tourist arrivals is also evident, suggesting a coevolutionary process underpinning TALC. This study adds to the nascent concept of multiplicity tourism-area lifecycles to denote an intricate web of linkages among different lifecycle traits of a destination. It improvises the concept of coactive development and paves the way for destination coevolution to articulate evolutionary interactions between tourists and tourism operators through reciprocal changes. [ABSTRACT FROM AUTHOR]

In this study, soapstone waste originated from craftsmanship activities was used as an alternative filler (0–30 wt%) for a high‐density polyethylene (PE) matrix. The aim of this paper is to understand the effect of the filler particles on crystallinity, thermal stability and thermo‐mechanical properties of this newly developed composite material. Physico‐chemical characterization was performed by x‐ray diffraction (XRD) and Fourier‐transform infrared (FTIR) spectroscopy. Thermogravimetric analysis (TGA), oxidation induction time (OIT) and dynamic mechanical thermal analysis (DMA) were performed to assess the effect of the filler on the themo‐mechanical properties of PE. Thermal stability, measured by TGA, was enhanced, while OIT values reduced with filler content. A significant increase on the storage modulus of the composites (up to 148% in comparison with unfilled PE) was observed and this reinforcing effect was even more prominent at higher temperatures. XRD analysis revealed that the degree of crystallinity improved significantly with soapstone loading, which explains the substantial increase in stiffness observed. Increased crystallinity is also associated with higher strength, reduced residual stress, and better dimensional stability of end products, which can be particularly attractive for pressure pipe applications. [ABSTRACT FROM AUTHOR]

Tissue from a 77-year-old man diagnosed with mesothelioma was referred with a request for identification of the presence of fibrous structures in tissue samples. The individual's work history including working as a "mucker" at a specific "industrial" talc mine. Ferruginous bodies in the tissue digests as well as asbestos fibers were found. A bulk sample of a talc containing product from that mine was also analyzed. The correlation between the unique asbestos mineral/fibrous content of the talc to which he was exposed and findings of the same type of asbestos found in his lung is discussed. The type of asbestos found (tremolite) is a "non-commercial" type of asbestos that has been identified in some talc deposits. Tremolite, like all forms of asbestos is a causative agent for mesothelioma-the disease from which this individual suffered. [ABSTRACT FROM AUTHOR]

Surfactants are usually used as grinding aids. However, surfactant foaming during the grinding process is rarely mentioned in the literature with no clarification of its effect on the grinding process. In this paper, the generation of foam during the grinding of talc and quartz, as two different minerals in their hardness and hydrophobicity, was observed in the presence of sodium dodecyl sulfonate (SDS). The effect of generated foam on the fineness of ground product under different grinding conditions such as solids%, grinding time, and pulp pH was investigated. The results indicated that the foam was formed during the grinding of both minerals. The foam volume depends not only on the presence of surfactant but also on the characteristics of the mineral along with grinding conditions. The foam was intense and more stable particularly at pH 10 and high solid content (i.e., 60% solids) in the case of talc due to its fineness and hydrophobicity that result in bubbles stabilization. Remarkably, there is no foam at acidic pH due to the high ionic strength that leads to bubble instability. Most importantly, the presence of surfactant foams improves the size reduction process by providing more dispersion of particles, as one of the grinding aid mechanisms, due to particle‐particle and particle‐SDS repulsive electrostatic forces. [ABSTRACT FROM AUTHOR]

A large amount of the polypropylene (PP) produced worldwide is used in the form of fibers. In this work, a new modification route for talc and PP is investigated, which is based on the in situ polymerization of a silane–siloxane monomer mixture on the surface of talc particles or PP pellets, respectively. The obtained modified talc and PP samples were used for the development of PP-talc composite drawn fibers. Tensile tests, thermogravimetry (TGA), and X-ray diffraction (XRD) were used for the characterization of the materials. It was observed that such a modification procedure resulted in the exfoliation of some talc particles. Enhanced tensile strength was observed for composite drawn fibers of a low talc content (1% with respect to PP) and a low modifier content (2% with respect to talc), while co-aggregation of talc and silicone may occur at high silicone and talc contents, resulting in the inferior mechanical performance of the corresponding composites. It was concluded that the produced silicone polymer simultaneously acts as a modifier, antioxidant, and compatibilizer. The proposed modification route is promising and should be further optimized. [ABSTRACT FROM AUTHOR]

The aim of the study was to experimentally verify the enhancement of certain mechanical properties of a composite material consisting of unsaturated polyester matrix reinforced with fiberglass, by incorporating specific proportions of sodium aluminosilicate (SAS) powders and talc as fillers for the fabrication of large wind turbine blades. Samples composed of these materials, with varying combinations of the added components, underwent testing for tensile and bending strength, and experiments were conducted to determine their modulus of elasticity. The findings indicate that the inclusion of SAS in the matrix material resulted in increased values of tensile strength and modulus of elasticity up to certain proportions. Solely adding talc to the matrix material led to a rise in bending strength. Increasing the talc percentage in the matrix material reinforced with 20% fiberglass resulted in decreased tensile strength and elastic modulus of the samples, while incorporating a blend of SAS and talc into the matrix material reinforced with 20% fiberglass significantly boosted the elastic modulus and tensile strength of the samples under tensile conditions. [ABSTRACT FROM AUTHOR]

Talc with particle sizes of 1250 mesh (Talc‐1250), 3000 mesh (Talc‐3000), and 5000 mesh (Talc‐5000), used as synergist, was added into transparent fireproof coatings applied in wood substrates, and the influence of talc particle size on the comprehensive properties of the coatings was analyzed carefully. The results show that adding talc exerts super synergistic effect on enhancing the flame retardancy and smoke release suppression properties in the resulting coatings, and the synergistic efficiency of talc is varied with the talc particle size. Fire resistance analysis shows that the MTPPE2 coating containing Talc‐3000 exhibits better synergistic effects, accompanying a minimum back temperature of 106.3°C at 900°C and a maximum intumescent factor of 116.3. SEM‐EDS and FTIR analyses show that adding Talc‐3000 in the MTPPE2 coating contributes to the formation of a more intumescent and compact char against fire concomitant with the highest P/C mass ratio of 0.36 in char. Transparency analysis shows that the transparency of the coatings gradually decreases with the decrease of talc particle size, and the Talc‐1250 with exfoliated morphology imparts less loss of transparency to the coating while the Talc‐3000 and Talc‐5000 with intercalated morphologies induce more obvious light scattering in the coatings. Highlights: Talc was used to enhance the comprehensive properties of transparent fireproof coatings.Synergistic efficiency of talc on the fire safety of coatings varies with its particle size.Talc with a particle size of 3000 mesh exerts an optimum synergism in the coatings.Transparency of the coatings gradually decreases as talc particle size decreases. [ABSTRACT FROM AUTHOR]

Ibiza is an island in the Western Mediterranean internationally known as a sun and beach tourist destination, and it is notable for its nightclubs. This fact is the result of a century of tourist history that began in the first third of the 20th century and reached its maximum data at the end of that century and the beginning of the 21st century. Using the tourism area life cycle (TALC) model as a reference, it is possible to affirm that Ibiza has already gone through most of the stages proposed by the TALC. The objective of this work is to undertake a historical approach to the events and context that this island experienced during the period that could be considered to be a consolidation stage (1977 to 2000), which is still little analyzed. During this period, demand growth continued, although at a slower pace than in the previous stages, and suffered the first major crisis. The regional administration had to face the errors of the previous decades with various legal actions as follows: the limitation of the accommodation supply, which was already oversized by that stage; the environmental protection of spaces that had not yet been affected by urban development; the modernization of the offerings, much of them being obsolete and degraded; and the diversification of the issuing markets, which had until then been focused on Germany and the United Kingdom. The economic crisis of the early 1990s was a turning point for the tourism sector, both in terms of administrations and companies, and quantitative growth was replaced by qualitative growth in the following years. Starting in 2000, tourism in Ibiza entered a new phase characterized by the modernization of the offerings and the stagnation of data. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective: Talc pleurodesis is a widely used treatment option for malignant pleural effusion (MPE). However, the optimal form of administration remains controversial. Thus, we performed a systematic review and meta-analysis to assess the effectiveness of talc slurry (TS) in comparison with thoracoscopic talc insufflation/poudrage (TTI) for MPE treatment. Methods: We searched PubMed, EMBASE, and Cochrane Library databases for studies that compared TS with TTI in patients with MPE. We used a random-effects model with a 95% CI to pool the data. Heterogeneity was assessed with I2 statistics. Results: We included eight studies involving 1,163 patients, 584 of whom (50.21%) underwent TS. Pleurodesis failure rates were similar between the procedures (OR = 1.07; 95% CI: 0.56-2.06; p = 0.83; I2 = 62%); and 68% of patients (95% CI: 0.31-1.47; p = 0.33; I2 = 58%) had postoperative complications, which were lower in patients in the TS group than in the TTI group. In a subgroup analysis considering only randomized clinical trials, the failure rate was significantly lower in the TS treatment group (OR = 0.62; 95% CI: 0.42-0.90; p = 0.01; I2 = 0%). Similarly, dyspnea was less common in the TS group (OR = 0.74; 95% CI: 0.41-1.34; p = 0.32; I2 = 55%). Adverse effects were reported in 86 patients, and no significant difference was seen between the TS and TTI groups: empyema (OR = 1.43; 95% CI: 0.36-5.64; p = 0.86; I2 = 0%), pain (OR = 1.22 (95% CI: 0.67-2.21; p = 0.51; I2 = 38%), and pneumonia (OR = 1.15; 95% CI: 0.30-4.46; p = 0.86; I2 = 27%). Conclusions: Our findings suggest that TS is an effective treatment for MPE, with no significant increase in adverse events. Results suggest equivalent efficacy and safety for both procedures.

In this work, we were decontaminated the ore to extract the talc, directly. Then, we used talc as a heterogeneous basic catalyst for one pot synthesis of bis(pyrazolyl)methane derivatives via the condensation of ethylacetoacetate, hydrazine hydrate and aromatic aldehyde derivatives under thermal and solvent-free conditions. This solid type of catalyst was identified by fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDS), EDS mapping and Brunauer–Emmett–Teller (BET) theory. Heterogeneous and solvent-free conditions, catalyst recyclability, high yields of the products and short reaction times are some advantages of this method. The reusability of the catalyst was examined for five times and it was successfully used in each run without any significant decreasing in its activity.

ObjectiveTo evaluate the associations between 10 well-established ovarian cancer risk factors and risk of ovarian cancer among women with vs. without endometriosis.DesignPooled analysis of 9 case-control studies in the Ovarian Cancer Association Consortium.SettingPopulation-based.Patient(s)We included 8,500 women with ovarian cancer, 13,592 control women.Intervention(s)Ten well-established ovarian cancer risk factors.Main outcome measure(s)Risk of ovarian cancer for women with and without endometriosis.Result(s)Most risk factor-ovarian cancer associations were similar when comparing women with and without endometriosis, and no interactions were statistically significant. However, body mass index (BMI) 25-

Magnetic separation has been proposed to greenly separate chalcopyrite and talc several decades ago, due to their extremely similar floatability of minerals. However, this approach was not achieved initially due to the inadequately magnetic induction of traditional magnetic separation, and fine particle size of chalcopyrite. Currently, the development of highly magnetic induction technology provides strong feasibility for this separation. In this work, we employed pulsating high-gradient magnetic separation (PHGMS) with highly magnetic induction (1.8T) to separate chalcopyrite and talc, and found that the PHGMS achieves a good separation of chalcopyrite from talc. But the chalcopyrite recovery decreased with the decrease of its particle size, and thus surface oxidation treatment was attempted to increase the magnetism and magnetic capture of ultrafine chalcopyrite. As a result, an increment of approximately 10 % was observed in the recovery of ultrafine chalcopyrite post-oxidation. As verified by the superconducting quantum interference device measurements, the oxidized ultrafine chalcopyrite exhibited a significant increase in the saturation magnetisation intensity, remanent magnetisation and coercivity values. Such magnetism enhancement is a result of the formation of paramagnetic Fe(III)–O–OH structures on the oxidized chalcopyrite surface, in terms of X-ray photoelectron spectroscopy and Mössbauer spectroscopy investigations. Furthermore, the density functional theory revealed that the formation of Fe(III)–O–OH structures caused a substantial increase in the magnetic moments of iron ions in antiferromagnetic chalcopyrite. These findings may extend the application of magnetic separation, and facilitate the flotation of ultrafine chalcopyrite from other minerals, at significantly reduced reagents use, and productive and environmental costs.

BackgroundRisk of ovarian cancer in women with frequent perineal talcum powder product is not well understood. Prior systematic reviews focused on ever use. The purpose of this study is to estimate the association between frequent (at least 2 times per week) perineal talcum powder use and ovarian cancer.MethodsA systematic review and meta-analysis was conducted according to meta-analysis of observational studies in epidemiology guidelines. Study protocol was prospectively registered at PROSPERO (registration number CRD42020172720). Searches were performed in PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials databases from their inception to August 2, 2021. Case-control and cohort studies were included if they reported frequent perineal talcum powder use and an adjusted odds ratio or hazard ratio for ovarian cancer. Review for inclusion, data extraction, and quality assessment (using the Newcastle-Ottawa Scale [NOS]) were performed independently by two reviewers. Pooled adjusted odds ratios with 95% confidence intervals were generated from the random effects model. Heterogeneity was quantified with I2 statistic. Funnel plot and Eger's test were performed to assess publication bias. Subgroup and sensitivity analyses were performed for testing the robustness of the overall findings.ResultsInitial database searches returned 761 unique citations and after review, eleven studies describing 66,876 patients, and 6542 cancers were included (Cohen's κ = 0.88). Publication quality was high (median NOS = 8, range: 4 to 9). Frequent talcum powder use was associated with an elevated risk of ovarian cancer (adjusted pooled summary odds ratio 1.47 (95% CI 1.31, 1.65, P