Diverse utilization of surfactants in coal-floatation for the sustainable development of clean coal production and environmental safety: a review

The rapidly increasing modern industrial world demands a huge uninterrupted energy supply, where high-quality coal (HQC) is one of the major sources of the required energy. In this regard, a gigantic amount of solid waste including ash and toxic chemicals, such as heavy metals, nitrate and sulphur, gases including NOx and SOx are emitted during the direct incineration process of low-rank coal. About 10 Gt of CO₂ and about one-fifth of total greenhouse gases in the world are emitted each year due to coal combustion in power plants, making it the single largest cause of climate change. The UN proposed that OECD countries stop producing electricity from coal by 2030 and the rest of the world by 2040. Herein, we discuss the development of modern technologies that can convert low-quality coal (LQC) into high-quality coal (HQC) to minimize the impact of fossil fuel burn, climate change, premature death of animals and all other related environmental hazards. Amongst the many established technologies, flotation pre-treatment is the most common and effective method used worldwide due to its lower energy input than other methods. In this review, we attempt to present an up-to-date understanding of the applications and utilities of surfactants in coal floating. We also demonstrate the possible modernization of this surfactant chemistry and its prospects.

The rapidly increasing modern industrial world demands a huge uninterrupted energy supply, where high-quality coal (HQC) is one of the major sources of the required energy.     

Carboxymethyl cellulose-based materials as an alternative source for sustainable electrochemical devices: a review

In electrochemistry, bio-based materials are preferred over the traditional costly and synthetic polymers due to their abundance, versatility, sustainability and low cost. One of the bio-based polymers is carboxymethyl cellulose (CMC) which has become an overarching material in electrochemical devices pertaining to its amphiphilic nature with multi-carbon functional groups. Owing to its flexible framework with fascinating groups on its surface like hydroxide (–OH) and carboxylate (–COO⁻), CMC is able to be modified into conducting materials by blending it with other biopolymers, synthetic polymers, salts, acids and others. This blending has improved the profile of CMC by exploiting the ability of hydrogen bonding, swelling, adhesiveness and dispersion of charges and ions. These properties of CMC have made it possible to utilize this bio-sourced polymer in several applications as a conducting electrolyte, binder in electrodes, detector, sensor and active material in fuel cells, actuators and triboelectric nanogenerators (TENG). Thus, CMC based materials are cheap, environment friendly, hydrophilic, biodegradable, non-toxic and biocompatible which render it a desirable material in energy storage devices.

This review describes the applications of CMC and superiority of other bio-based materials over the traditional costly and synthetic polymers in electrochemistry due to their abundance, versatility, sustainability and low cost.     

Mechanistic evaluation of phytochemicals in breast cancer remedy: current understanding and future perspectives

Breast cancer is one of the most commonly diagnosed cancers around the globe and accounts for a large proportion of fatalities in women. Despite the advancement in therapeutic and diagnostic procedures, breast cancer still represents a major challenge. Current anti-breast cancer approaches include surgical removal, radiotherapy, hormonal therapy and the use of various chemotherapeutic drugs. However, drug resistance, associated serious adverse effects, metastasis and recurrence complications still need to be resolved which demand safe and alternative strategies. In this scenario, phytochemicals have recently gained huge attention due to their safety profile and cost-effectiveness. These phytochemicals modulate various genes, gene products and signalling pathways, thereby inhibiting breast cancer cell proliferation, invasion, angiogenesis and metastasis and inducing apoptosis. Moreover, they also target breast cancer stem cells and overcome drug resistance problems in breast carcinomas. Phytochemicals as adjuvants with chemotherapeutic drugs have greatly enhanced their therapeutic efficacy. This review focuses on the recently recognized molecular mechanisms underlying breast cancer chemoprevention with the use of phytochemicals such as curcumin, resveratrol, silibinin, genistein, epigallocatechin gallate, secoisolariciresinol, thymoquinone, kaempferol, quercetin, parthenolide, sulforaphane, ginsenosides, naringenin, isoliquiritigenin, luteolin, benzyl isothiocyanate, α-mangostin, 3,3′-diindolylmethane, pterostilbene, vinca alkaloids and apigenin.

Breast cancer is one of the most commonly diagnosed cancers around the globe and accounts for a large proportion of fatalities in women.     

Reference materials for molecular diagnostics: Current achievements and future strategies

BackgroundMolecular diagnoses have become more widespread in many areas of laboratory medicine where qualitative or quantitative approaches are used to detect nucleic acids. The increasing number of assay methods and the targets for molecular diagnostics contribute to variability in the test results among clinical laboratories. Thus, reference materials (RMs) are required to enhance the comparability of results.MethodsThis review focuses on the definition of RMs as well as the production and characteristics of higher order RMs from different organizations and their future strategies.ResultsWe describe the recent progress in RMs, including the definition of RMs by the Joint Committee for Guides in Metrology, as well as the production and characteristics of higher order RMs by international official bodies.ConclusionsThere is an urgent need for RMs in nucleic acid testing, especially higher order RMs. To advance the harmonization and standardization of clinical nucleic acid detection, cooperation between the above organizations is proposed and different approaches to higher order RMs development are also needed.     

Oxidative coupling of bio-alcohols mixture over hierarchically porous perovskite catalysts for sustainable acrolein production

The acrolein production from bio-alcohols methanol and ethanol mixtures using AMnO₃ (since A = Ba and/or Sr) perovskite catalysts was studied. All the prepared samples were characterized by XRD, XPS, N₂ sorption, FTIR, Raman spectroscopy, TEM, SEM, TGA, and NH₃–CO₂-TPD. The catalytic oxidation reaction to produce acrolein has occurred via two steps, the alcohols are firstly oxidized to corresponding aldehydes, and then the aldol is coupled with the produced aldehydes. The prepared perovskite samples were modified by doping A (Sr) position with (Ba) to improve the aldol condensation. The most catalytic performance was achieved using the BaSrMnO₃ sample in which the acrolein selectivity reached 62% (T = 300 °C, MetOH/EtOH = 1, LHSV = 10 h⁻¹). The increase in acrolein production may be related to the high tendency of BaSrMnO₃ toward C–C coupling formation. The C–C tendency attributes to that modification have occurred in acid/base sites because of metal substitution.

The figure illustrates the potential of perovskite as a catalyst for acrolein production via simultaneous oxidative coupling of renewable alcohols (ethanol and methanol) followed by aldol condensation of pre-formed aldehydes to form acrolein.     

Stability of organometal halide perovskite solar cells and role of HTMs: recent developments and future directions

Perovskite solar cells (PSCs) have recently emerged as one of the most exciting fields of research of our time, and the World Economic Forum in 2016 recognized them as one of the top 10 technologies in 2016. With 22.7% power conversion efficiency, PSCs are poised to revolutionize the way power is produced, stored and consumed. However, the widespread use of PSCs requires addressing the stability issue. Therefore, it is now time to focus on the critical step i.e. stability under the operating conditions for the development of a sustainable and durable PV technology based on PSCs. In order to improve the stability of PSCs, hole transport materials (HTMs) have been considered as the paramount components. This is due to the fact that most of the organic HTMs possess a hygroscopic and acidic nature that leads to poor stability of the PSCs. This article reviews briefly but comprehensively the environmental stability issues of PSCs, fundamentals, strategies for improvement, the role of HTMs towards stability and various types of HTMs. Also the environmental parameters affecting the performance of perovskite solar cells including temperature, moisture and light soaking environment have been considered.

This article gives the comprehensive review on the environmental stability issues of PSCs.     

Additive manufacturing technology of polymeric materials for customized products: recent developments and future prospective

The worldwide demand for additive manufacturing (AM) is increasing due to its ability to produce more challenging customized objects based on the process parameters for engineering applications. The processing of conventional materials by AM processes is a critically demanded research stream, which has generated a path-breaking scenario in the rapid manufacturing and upcycling of plastics. The exponential growth of AM in the worldwide polymer market is expected to exceed 20 billion US dollars by 2021 in areas of automotive, medical, aerospace, energy and customized consumer products. The development of functional polymers and composites by 3D printing-based technologies has been explored significantly due to its cost-effective, easier integration into customized geometries, higher efficacy, higher precision, freedom of material utilization as compared to traditional injection molding, and thermoforming techniques. Since polymers are the most explored class of materials in AM to overcome the limitations, this review describes the latest research conducted on petroleum-based polymers and their composites using various AM techniques such as fused filament fabrication (FFF), selective laser sintering (SLS), and stereolithography (SLA) related to 3D printing in engineering applications such as biomedical, automotive, aerospace and electronics.

The worldwide demand for additive manufacturing (AM) is increasing due to its ability to produce more challenging customized objects based on the process parameters for engineering applications.     

Polysulfides made from re-purposed waste are sustainable materials for removing iron from water

Water contaminated with Fe³⁺ is undesirable because it can result in discoloured plumbing fixtures, clogging, and a poor taste and aesthetic profile for drinking water. At high levels, Fe³⁺ can also promote the growth of unwanted bacteria, so environmental agencies and water authorities typically regulate the amount of Fe³⁺ in municipal water and wastewater. Here, polysulfide sorbents—prepared from elemental sulfur and unsaturated cooking oils—are used to remove Fe³⁺ contaminants from water. The sorbent is low-cost and sustainable, as it can be prepared entirely from waste. The preparation of this material using microwave heating and its application in iron capture are two important advances in the growing field of sulfur polymers.

A polymer prepared by co-polymerisation of sulfur and canola oil removed Fe³⁺ from water. Microwave irradiation was convenient in promoting the polymerisation.

The removal of iron from groundwater, potable water and wastewater is an important requirement for water authorities, industry, and environmental agencies.¹ Ferric iron (Fe³⁺) in particular is undesirable because it leads to discolouration of plumbing fixtures^2,3 and imparts unappealing odour and taste to drinking water.² Additionally, Fe³⁺ promotes the growth of certain bacteria, leading to fouling, clogging of pipes and other undesirable ecological effects.⁴ There are also some indications that adverse health effects in aquatic life may originate from high levels of iron.^5,6 The control of iron content in water is therefore an important economic and environmental issue, with levels typically regulated by government authorities.^7,8 There are several methods for removing iron from water including ion exchange,⁹ oxidative precipitation with subsequent flocculation and/or filtration,^10,11 and adsorption of iron onto activated carbon,¹² among other techniques.¹ However, in scenarios where large volumes of water are treated, these methods may be expensive, low in performance, or both.¹Our interest in controlling iron content in water stemmed from a recent engagement with an industry partner facing a challenge in meeting regulatory requirements for iron levels in groundwater pumped and discharged from an underground operations centre. A combination of oxidative conversion of Fe²⁺ to Fe³⁺ and separation using flocculants and filters provided some success in meeting the 3 mg L⁻¹ daily discharge limit, but alternative low-cost methods were desired to facilitate the treatment and discharge of more than 150 000 L per day containing iron levels in the range of 35–60 mg L⁻¹. Our laboratory has recently reported the use of inexpensive polymers made from elemental sulfur and their use in sequestering metals such as palladium and mercury.^13–15 It was therefore intriguing scientifically, economically and environmentally to determine if these polymers were suitable in the removal of iron from water.Sulfur polymers, especially those prepared by inverse vulcanisation and related processes,¹⁶ have emerged as versatile materials in diverse areas of science.^15–20 These studies are motivated, at least in part, by the megaton stores of sulfur available from crude oil desulfurisation.^21,22 In converting this petroleum by-product into useful polymers, interesting applications have since been reported in power generation^23,24 and storage,¹⁶ high refractive index and IR transmitting optical devices,^25–27 dynamic and healable materials,^26,28 thermal insulation,²⁹ sulfur-doped carbon materials,³⁰ and heavy metal remediation.^{13,14,29–33}In the case of metal binding, polysulfide polymers have been used primarily to sequester highly toxic mercury salts.^{13,14,31–33} Because these sulfur polymers are simple to prepare in a single chemical step, we hypothesised that even if the affinity of the polysulfide for the harder Fe³⁺ is lower than for the softer Hg²⁺, the polymer may still be useful in removing the former metal from water. This hypothesis is further motivated by Theato''s recent discovery that while high-sulfur polymers are excellent at capturing mercury, there is still appreciable binding to Fe³⁺ for an electrospun blend of a poly(sulfur-statistical-diisopropenylbenzene) polysulfide and poly(methyl methacrylate).³²We therefore set out to assess the iron-binding properties of a different co-polymer prepared by the direct reaction of elemental sulfur and canola oil. Importantly, this co-polymer is sustainably synthesised using only sulfur and the widely available and renewable canola oil.^34–36 The resulting material is an elastomeric, high-sulfur factice³⁷ that has previously been studied by Theato as a novel cathode material³⁸ and by our team as a reactive sorbent for mercury pollution.¹⁴ Should this material prove effective in removing Fe³⁺ from water, it would represent a cost-effective method for water treatment through waste valorisation.As a starting point, the canola oil polysulfide was synthesised by first heating sulfur to 180 °C in order to promote radical ring-opening polymerisation.¹⁴ Canola oil was then added to the polysulfide pre-polymer to cross-link the sulfur chains. The reaction mixture typically reaches its gel point within 20 minutes, at which time the reaction is cooled to provide a rubber-like material. The synthesis was prepared for 50%, 60%, and 70% sulfur by mass. The polymer was then milled into 1.0–2.5 mm diameter particles for subsequent use (Fig. 1 and S4^†). Analysis of the polymers by infrared spectroscopy and Raman spectroscopy were consistent with our previous report on the material, in which the key polysulfide structure (S–S bonds) and canola oil backbone groups (e.g. C O) are evident (S5–S6^†).¹⁴ Thermogravimetric analysis and differential scanning calorimetry were also consistent with that previously reported for these materials, with major decompositions initiated over 200 °C. The first of these decompositions corresponds to thermal breakdown of S–S bonds and the second major mass loss above 300 °C corresponds to the decomposition of the remaining canola oil domain of the polymer (S7^†). SEM analysis of the polysulfides indicated a smooth polymer surface embedded with high-sulfur micron scale particles (S8–S10^†).^14,38Open in a separate windowFig. 1A canola oil polysulfide was prepared by direct reaction of canola oil and elemental sulfur. The material was prepared with 50, 60, and 70% sulfur by mass for subsequent iron sorption studies (50% sulfur polymer shown). An approximate structure of canola oil is shown, with oleic acid as the major fatty acid in the triglyceride.With the polymer in hand, we then tested its ability to bind to and remove Fe³⁺ from water. An aqueous solution of FeCl₃ was prepared at a concentration of 50 mg L⁻¹ and then equilibrated for 48 hours. The resulting solution (pH 3.0) could be monitored by its absorbance at 306 nm. At this composition, the Fe³⁺ is fully soluble so that any reduction in iron content over time could be attributed to binding to the polymer, rather than precipitation. Accordingly, 2.0 g of the polysulfide was added to a 20 mL sample of the Fe³⁺ solution to benchmark iron removal efficiency. After 24 hours of incubation with gentle agitation (end over end mixing), the absorbance of the solution at 310 nm was measured to determine the amount of Fe³⁺ captured by the polymer. The concentration of the iron was typically reduced to between 3 and 6 mg L⁻¹ for all polymer samples (50, 60 and 70% sulfur, S11–S12^†). Subsequent experiments were therefore restricted to the polysulfide prepared at 50% sulfur, 50% canola oil by mass. At this composition, the particles are more elastic and durable; at higher levels of sulfur the particles become more brittle.The amount of polymer in these initial tests (2.0 g per 20 mL of water) was somewhat arbitrary, but subsequent testing revealed that this mass was indeed required to reduce the iron concentration below 10 mg L⁻¹ (S13–S14^†). SEM and XRD analysis of the polymer after the water treatment revealed no morphological change (S15–S16^†), indicating stability of the polymer structure during the treatment. It should also be noted that relatively low levels of iron are actually bound to the polymer (less than 1 mg Fe³⁺ per 2 g of polymer in these experiments). Nevertheless, the ease at which this polymer can be prepared on relatively large scales allowed a demonstration of a 1 L scale water purification in which the iron concentration was reduced from 50 mg L⁻¹ to 1.3 mg L⁻¹, as measured independently by UV-vis analysis and atomic absorption spectroscopy (Fig. 2). Furthermore, exposing the polymer to hydrogen peroxide did not reduce its ability to remove Fe³⁺ from water—an important feature that makes the material compatible with many iron removal process that rely on the conversion of Fe²⁺ to Fe³⁺ through reaction with hydrogen peroxide (S17–S18^†). This demonstration is important because the polymer was not effective in removing Fe²⁺ from water, with no significant reduction in Fe²⁺, as indicated by AAS (S21^†). Another beneficial feature of the polymer (in comparison to elemental sulfur) is that the polymer particles are not prone to caking, which makes filtration a straightforward process (S20^†).Open in a separate windowFig. 2A 1.0 L solution of Fe³⁺ (50 mg L⁻¹) was treated with 200 g of the non-porous canola oil polysulfide (50% sulfur) for 24 hours at 23 °C. The polymer reduced the iron concentration to 1.3 mg L⁻¹, as measured independently by UV-vis spectroscopy and atomic absorption spectroscopy (AAS). After removing the polysulfide by filtration, the treated water appears colourless. See S19^† for additional details.Because relatively large amounts of the polysulfide are required to remove Fe³⁺ from water, we anticipated that increasing surface area would improve its performance. Accordingly, a porous version of the polysulfide was prepared by reacting sulfur and canola oil in the presence of a large excess of a sodium chloride porogen (70% of the reaction mixture is sodium chloride). Soaking the resulting product in water removes the porogen, leaving micron scale pores and channels in the polysulfide material (Fig. 3a and S22^†). This material was consistent in its thermal and spectroscopic properties to those previously reported when it was prepared for mercury sorption (S22–S24^†).¹⁴ This material was also stable across a wide pH range at 25 °C, with minimal decomposition after incubation for 7 days in water at pH 1, 6 or 13, as indicated by visual inspection and ¹H NMR analysis (S25–S27^†).Open in a separate windowFig. 3A porous version of the canola oil polysulfide was prepared by reacting canola oil and sulfur in the presence of a sodium chloride porogen. Sodium chloride was removed from the polymer by washing with water, resulting in a polymer with micron-scale pores. (a) Photograph and SEM micrograph of the porous canola oil polysulfide. (b) Fe³⁺ sorption over time for the porous polysulfide (green plot) and non-porous polysulfide (blue plot). The iron concentration did not change if no polymer was added to the solution (red plot).With the porous canola oil polysulfide in hand, the Fe³⁺ capture experiments were repeated and compared to the non-porous polymer. The porous polymer was superior in the rate of Fe³⁺ removal from water and less polymer was required. For example, 2.0 g of the porous polysulfide was able to reduce the Fe³⁺ concentration in a 20 mL sample from 50 mg L⁻¹ to 3 mg L⁻¹ in 2 hours (Fig. 3b). It was also demonstrated that only 1.0 g of the polymer was required to reduce the concentration of Fe³⁺ from 50 mg L⁻¹ to 3 mg L⁻¹ for 20 mL of contaminated water (S28–S30^†). Fitting the sorption data to a Langmuir isotherm model indicated a sorption capacity of 0.8 mg g⁻¹ (S31^†). The reduction of iron concentration was also demonstrated across a pH range of 1 to 10, though precipitation also accounts for the reduction in iron concentration above pH 3.0 (S32^†). Even in these cases, the polysulfide is beneficial and serves as a filtration media to prevent caking when removing precipitated iron salts by filtration. Importantly, the polysulfide''s ability to remove iron from water was not impacted by the presence of other common ions such as Na⁺, K⁺, Mg²⁺, Ca²⁺, and Cl⁻, even when all were present at 10 mg L⁻¹ in the Fe³⁺ solution (S33–S34^†).If the polymer was re-used in the same iron sorption experiment, the sorption capacity dropped significantly with 95% Fe³⁺ removal on the first run and 62% and 26% on the second and third uses, respectively (S36^†). This result suggests that the polymer is best deployed as a single use material in Fe³⁺ binding. Fortunately, when the polymer was prepared from waste cooking oil and sulfur (S37–S39^†), it was equally as effective in removing Fe³⁺ from water (S40^†). This result means that even though the polymer is best used for a single water treatment, this is a productive example of waste valorisation. We are currently investigating how the polymer–iron complex can be re-purposed yet again as an additive in construction materials and novel composites.To deploy sulfur polymers for applications in water purification and environmental chemistry, it is useful to have methods to prepare the material rapidly and on-demand. Because sulfur-based polymers are excellent thermal insulators,²⁹ it is difficult to ensure even and reliable heating during the polymerisation. Addressing this issue, we investigated whether microwave irradiation would be practical in the synthesis of the canola oil polysulfide. Because canola oil and unsaturated triglycerides can be heated rapidly with microwave irradiation, we hypothesised that this might be a convenient strategy for heating the reaction mixture. Indeed, both laboratory microwave reactors with precise temperature and power control (S41–S42^†) and conventional household microwave ovens (Fig. 4 and S43^†) were highly effective for the rapid heating and subsequent co-polymerisation of canola oil and sulfur. For instance, when the polymerisation was carried out in an 1100 W household microwave oven, the polymer was formed within a mere 5 minutes. The spectroscopic, thermal and Fe³⁺ binding properties of the material synthesised in the microwave reactor were no different from the material prepared through the slower conventional heating (S43–S47^†). The ability to prepare these polymers in a conventional microwave may be important in scaling up the synthesis of these polymers because several batches could be prepared in rapid succession or through the use of several inexpensive microwave reactors operating in parallel. This process might also make the polysulfide accessible in areas with limited resources—an important consideration when the polymers will be used to remove heavy metals from water.¹⁴Open in a separate windowFig. 4(a) Reaction mixture to form a porous polysulfide: canola oil (15.0 g), sulfur (15.0 g), and sodium chloride (70.0 g). (b) Product of polymerisation after irradiation in a household microwave (1100 W) for 5 minutes. (c) Porous polysulfide obtained after removing the sodium chloride porogen with a water wash.In summary, a polysulfide material made from canola oil and sulfur was used to remove Fe³⁺ from water. The iron removal was tested at industrially relevant concentrations and purified to levels within the limits of environmental regulatory agencies. A rapid and scalable synthesis of the polysulfide was also executed in a microwave reactor—an important milestone in the synthesis of high-sulfur polymers because of the challenge in reliably and evenly heating these thermally insulating materials. More generally, because the featured polymer can be made entirely from industrial waste, this study is an advance in sustainable chemistry, waste valorisation, and environmental chemistry.     

Introducing random bio-terpene segments to high cis-polybutadiene: making elastomeric materials more sustainable

In this work, we explore the statistical copolymerization of 1,3-butadiene with the terpenic monomers myrcene and farnesene, carried out via coordination polymerization using a neodymium-based ternary catalytic system. The resultant copolymers, poly(butadiene-co-myrcene) and poly(butadiene-co-farnesene), were synthesized at different monomer ratios, elucidating the influence of the bio-based monomer content over the kinetic variables, molecular and thermal properties, and the reactivity constants (Fineman–Ross and Kelen–Tüdös methods) of the resultant copolymers. The results indicate that through the herein employed conditions, it is possible to obtain “more sustainable” high-cis (≈95%) polybutadiene elastomers with random and tunable content of bio-based monomer. Moreover, the polymers exhibit fairly high molecular weights and a rather low dispersity index. Upon copolymerization, the T_g of high-cis PB can be shifted from −106 to −75 °C (farnesene) or −107 to −64 °C (myrcene), without altering the microstructure control. This work contributes to the development of more environmentally friendly elastomers, to form “green” rubber materials.

In this work, we explore the statistical copolymerization of 1,3-butadiene with the terpenic monomers myrcene and farnesene, carried out via coordination polymerization using a neodymium-based ternary catalytic system.     

Protein nanofibrils and their use as building blocks of sustainable materials

The development towards a sustainable society requires a radical change of many of the materials we currently use. Besides the replacement of plastics, derived from petrochemical sources, with renewable alternatives, we will also need functional materials for applications in areas ranging from green energy and environmental remediation to smart foods. Proteins could, with their intriguing ability of self-assembly into various forms, play important roles in all these fields. To achieve that, the code for how to assemble hierarchically ordered structures similar to the protein materials found in nature must be cracked. During the last decade it has been demonstrated that amyloid-like protein nanofibrils (PNFs) could be a steppingstone for this task. PNFs are formed by self-assembly in water from a range of proteins, including plant resources and industrial side streams. The nanofibrils display distinct functional features and can be further assembled into larger structures. PNFs thus provide a framework for creating ordered, functional structures from the atomic level up to the macroscale. This review address how industrial scale protein resources could be transformed into PNFs and further assembled into materials with specific mechanical and functional properties. We describe what is required from a protein to form PNFs and how the structural properties at different length scales determine the material properties. We also discuss potential chemical routes to modify the properties of the fibrils and to assemble them into macroscopic structures.

Protein nanofibrils produced from renewable resources provide opportunities to create novel materials for sustainable development.     

Night shift: can a homeopathic remedy alleviate shift lag?

Night shift nurses are subject to shift lag or circadian dysrhythmia, which may result in physical and mental symptoms ranging from fatigue, irritability, depression, and apathy to gastrointestinal, cardiovascular, and sleep disorders. This study investigated the effect a homeopathic remedy No-Shift-Lag had on the night shift nurses in an intensive care unit. The study was a randomized, double-blind, placebo-controlled, crossover trial. The measures included an objective computer-based vigilance test and a series of subjective questionnaires.