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AbstractThis paper discusses the current challenges of exploration of outer planets and proposes a nuclear thermal propulsion (NTP) system for future deep space exploration missions. The mission design problem with respect to the NTP system is presented where it is proposed that NTP-powered missions need to integrate the requirements and constraints of mission objective, spacecraft design, NTP system design, and launch vehicle limits into a self-consistent model. The paper presents a conceptual NTP-powered rendezvous mission to Neptune that uses a single high-performance–class commercial launch vehicle to deliver over 2 mT of useful payload in a direct transfer trajectory with total trip time being under 16 years.

Purpose: Smooth and autonomous navigation of mobile robot in a cluttered environment is the main purpose of proposed technique. That includes localization and path planning of mobile robot. These are important aspects of the mobile robot during autonomous navigation in any workspace. Navigation of mobile robots includes reaching the target from the start point by avoiding obstacles in a static or dynamic environment. Several techniques have already been proposed by the researchers concerning navigational problems of the mobile robot still no one confirms the navigating path is optimal. Design/methodology/approach: Therefore, the modified grey wolf optimization (GWO) controller is designed for autonomous navigation, which is one of the intelligent techniques for autonomous navigation of wheeled mobile robot (WMR). GWO is a nature-inspired algorithm, which mainly mimics the social hierarchy and hunting behavior of wolf in nature. It is modified to define the optimal positions and better control over the robot. The motion from the source to target in the highly cluttered environment by negotiating obstacles. The controller is authenticated by the approach of V-REP simulation software platform coupled with real-time experiment in the laboratory by using Khepera-III robot. Findings: During experiments, it is observed that the proposed technique is much efficient in motion control and path planning as the robot reaches its target position without any collision during its movement. Further the simulation through V-REP and real-time experimental results are recorded and compared against each corresponding results, and it can be seen that the results have good agreement as the deviation in the results is approximately 5% which is an acceptable range of deviation in motion planning. Both the results such as path length and time taken to reach the target is recorded and shown in respective tables. Originality/value: After literature survey, it may be said that most of the approach is implemented on either mathematical convergence or in mobile robot, but real-time experimental authentication is not obtained. With a lack of clear evidence regarding use of MGWO (modified grey wolf optimization) controller for navigation of mobile robots in both the environment, such as in simulation platform and real-time experimental platforms, this work would serve as a guiding link for use of similar approaches in other forms of robots.

Fuzzy logic is widely known as a value-based technique. Whale optimization algorithm (WOA), on the other hand, is a nature-inspired optimization technique. Hybridization of these two techniques is proposed for path planning and control, over multiple mobile robots in static and dynamic environments. The effectiveness of the resulting technique, known as ‘Fuzzy-WOA’, is tested through MATLAB simulation coupled with real-time experiments. Upon testing, a good agreement is observed between these platforms. Furthermore, the proposed technique is found to be more efficient when compared to other existing techniques, with a significant improvement of about 20.63% in terms of path lengths.

Purpose: This study aims to modify a nature-based numerical method named the invasive weed optimization (IWO) method for mobile robot path planning in various complex environments. Design/methodology/approach: The existing IWO method is quick in converging to a feasible solution but in a complex environment; it takes more time as well as computational resources. So, in this paper, the computational part of this artificial intelligence technique is modified with the help of recently developed evolution algorithms like particle swarm optimization, genetic algorithm, etc. Some conditional logic statements were used while doing sensor-based mapping for exploring complex paths. Implementation of sensor-based exploration, mathematical IWO method and prioritizing them for better efficiency made this modified IWO method take complex dynamic decisions. Findings: The proposed modified IWO is better for dynamic obstacle avoidance and navigating a long complex map. The deviation of results in simulation and experiments is less than 5.5%, which validates a good agreement between simulation and real-time testing platforms. Originality/value: As per a deep literature review, it has found that the proposed approach has not been implemented on the Khepera-III robot for smooth motion planning. Here a dynamic obstacle mapping feature is implemented. A method to selectively distribute seeds instead of a random normal distribution is also implemented in this work. The modified version of IWO is coded in MATLAB and simulated through V-Rep simulation software. The integration of sensors was done through logical conditioning. The simulation results are validated using real-time experiments.

Aim: Present research work focuses on the improvement of biopharmaceutical properties of aceclofenac (ACF) by the cocrystal approach. Background: ACF is one of the frequently used Nonsteroidal Anti-Inflammatory Drugs (NSAID). ACF is a BCS Class - II drug (low solubility and high permeability) with poor solubility and low oral bioavailability. Hence, the improvement in solubility and bioavailability of ACF is very crucial for successful product development. Nowadays, pharmaceutical cocrystals are considered a novel solid form of drugs. These cocrystals may have different physicochemical as well as biopharmaceutical properties as compared to the parent drug. In a previous study, the cocrystal of ACF (ACF-l-CYS NG and ACF-UREA NG) was successfully prepared and characterized. These cocrystals have shown superior solubility and dissolution rate than pure ACF in HCl buffer (pH 1.2). The synthesized cocrystals were also found non-hygroscopic and stable for 6 months under standard test settings. However, pharmacokinetic evaluation of these cocrystals has not been explored yet. Objective: The specific objective of this research work was the measurement of bioavailability and other pharmacokinetic parameters of ACF cocrystals prepared by the mechanochemical grinding method. Methods: Cocrystals of ACF with l-cystine and urea were prepared by neat grinding (NG) method and in-vivo oral bioavailability of prepared cocrystals was measured in Wistar rats. The plasma drug concentration was measured by high-performance liquid chromatography (HPLC), and the pharmacokinetic data was analyzed by “PK solver” software. Results: Percent relative bioavailability of ACF-l-CYS NG and ACF-UREA NG cocrystals in Wistar rats was found to be 242.05 ± 65.27and 178.93 ± 45.21 respectively, which were significantly higher (ANOVA, P < 0.05) than that of pure ACF. Conclusion: The present study indicates that the enhanced aqueous solubility of the prepared cocrystals leads to enhanced oral bioavailability of ACF. Thus, the cocrystals may be an alternative crystalline form of the drug that can enhance the solubility, dissolution rate, and oral bioavailability of many poorly soluble drugs.

Aim: Current work focuses on the improvement of the solubility and dissolution of ACF by the cocrystal approach. Background: Aceclofenac (ACF) is one of the commonly used Nonsteroidal Anti-Inflammatory Drug (NSAID) representing a variety of therapeutic applications including management of pain, inflammation, rheumatoid arthritis, and osteoarthritis, etc. But very low solubility and dissolution rate of ACF compromise its therapeutic utility. Now a day’s cocrystallization technique has emerged as a novel technique for modulation of the said problems. Objective: The Specific objectives of this research work were mechanochemical synthesis, characterization, and performance evaluation of aceclofenac cocrystal. Methods: ACF was screened with various pharmaceutically acceptable coformers (Selected from GRAS and EAFUS list) using MOPAC software and physical screening method to find out novel cocrystals of ACF with enhanced solubility and dissolution rate. Novel cocrystals (multi-component crystalline solid) of ACF with l-cystine were prepared by a neat grinding method and by liquid assisted grinding method. The synthesized cocrystals (ACF-l-CYS NG and ACF-l-CYS LAG) were characterized carefully by Differential Scanning Calorimetry (DSC), Infrared Spectroscopy (IR), and Powder XRay Diffraction (PXRD) to verify the formation of the cocrystals. Pharmaceutically significant properties such as powder dissolution rate, solubility, and stability of the prepared cocrystals were evaluated. Results: Compared to pure ACF, the prepared cocrystals showed superior solubility and dissolution rate. The prepared cocrystals were found to be stable and non-hygroscopic under study conditions. Conclusion: The cocrystallization technique was successfully utilized to increase the solubility and dissolution rate of aceclofenac.

The effects of mono- and divalent ions (Li+, K+, Na+, Cs+, Mg2+, Ca2+, Mn2+, Zn2+) on the binding of phosphoenolpyruvate (PEP) to rabbit muscle pyruvate kinase (PK) were studied by attenuated total reflection infrared spectroscopy in combination with a dialysis accessory. The experiments assessed the structural change of the protein as well as the binding mode of PEP. They indicated that a signal at 1638 cm–1assigned to a β sheet was perturbed differently with Na+as compared to the other monovalent ions. Otherwise, we obtained similar conformational changes in the presence of different monovalent cations, and therefore, it seems unlikely that the ion effects on activity are due to an ion effect on the structure of the PEP:PK complex. With different divalent cations, a particularly large conformational change was observed with Mn2+and attributed to a more closed conformation of the complex. The absorption of bound PEP was also detected. The antisymmetric stretching vibration of the carboxylate group of bound PEP indicates a more homogeneous binding mode for Mn2+compared to the other divalent ions. The symmetric stretching vibration depends on both monovalent and divalent ions, indicating that the dihedral angle O–C1–C2–O is affected by the ions in the catalytic site. Little change in the bond strengths of PEP is observed, indicating that the PEP:PK complex does not adopt a reactive conformation.

It is critical to obtain a coherent medical history, yet older patients are often vexing historians, presenting unique challenges. The roots of these challenges are complex, and must be understood [...]

The article focuses on the Indian Institute of Mass Communication (IIMC) in Delhi IIMC opened more than six decades ago on August 17, 1965. It refers to IIMC' state-of-the-art infrastructure including a community radio, television studios and research centre. It highlights a comment by IIMC director general K.G. Suresh regarding the 2017-18 session.

Background: Cancer is a major global health issue. It causes extensive individual suffering and gives a huge burden on the health care in society. Despite extensive research and different tools have been developed it still remains a challenge for early detection of this disease. FTIR imaging has been used to diagnose and differentiate the molecular differences between normal and diseased tissues. Methods: Fourier Transform Infrared Spectroscopy (FTIR) is able to measure biochemical changes in tissue, cell and biofluids based on the vibrational signature of their components. This technique enables to the distribution and structure of lipids, proteins, nucleic acids as well as other metabolites. These differences depended on the type and the grade of cancer. Results: We emphasize here, that the FTIR spectroscopy and imaging can be considered as a promising technique and will find its place on the detection of this dreadful disease because of high sensitivity, accuracy and inexpensive technique. Now the medical community started using and accepting this technique for early stage cancer detection. We discussed this technique and the several challenges in its application for the diagnosis of cancer in regards of sample preparations, data interpretation, and data analysis. The sensitivity of chemotherapy drugs on individual specific has also discussed. Conclusion: So far progressed has done with the FTIR imaging in understanding of cancer disease pathology. However, more research is needed in this field and it is necessary to understand the morphology and biology of the sample before using the spectroscopy and imaging because invaluable information to be figured out.

An interview is presented with Human Resource Development Minister of India, Prakash Javadekar. Topics discussed include challenges surrounding the appointment of teachers on contract bases under Sarva Shiksha Abhiyan; status of primary school teacher vacancies in the country; and steps Centre taking on primary education.

Actin filaments have key roles in cell motility but are generally claimed to be passive interaction partners in actin-myosin-based motion generation. Here, we present evidence against this static view based on an altered myosin-induced actin filament gliding pattern in an in vitro motility assay at varied [MgATP]. The statistics that characterize the degree of meandering of the actin filament paths suggest that for [MgATP] ≥ 0.25 mM, the flexural rigidity of heavy meromyosin (HMM)-propelled actin filaments is similar (without phalloidin) or slightly lower (with phalloidin) than that of HMM-free filaments observed in solution without surface tethering. When [MgATP] was reduced to ≤0.1 mM, the actin filament paths in the in vitro motility assay became appreciably more winding in both the presence and absence of phalloidin. This effect of lowered [MgATP] was qualitatively different from that seen when HMM was mixed with ATP-insensitive, N-ethylmaleimide-treated HMM (NEM-HMM; 25–30%). In particular, the addition of NEM-HMM increased a non-Gaussian tail in the path curvature distribution as well as the number of events in which different parts of an actin filament followed different paths. These effects were the opposite of those observed with reduced [MgATP]. Theoretical modeling suggests a 30–40% lowered flexural rigidity of the actin filaments at [MgATP] ≤ 0.1 mM and local bending of the filament front upon each myosin head attachment. Overall, the results fit with appreciable structural changes in the actin filament during actomyosin-based motion generation, and modulation of the actin filament mechanical properties by the dominating chemomechanical actomyosin state.

Different constructed wetland microcosm units have been designed in single as well as in combinations to study their performance for domestic wastewater treatment. Further, the integration potential of constructed wetland microcosms technology with up-flow anaerobic sludge blanket (UASB) and fluidized aerobic bed (FAB) reactors as a polishing unit was also studied. From the study, it is evaluated that the maximum removal efficiency of all selected parameters such as biochemical oxygen demand (BOD), total phosphorus (TP), soluble reactive phosphorus (SRP), ammonium (NH4+–N), nitrate (NO3−–N) and nitrite (NO2−–N) was expressed by the mixed planting unit of Pistia Stratiotesand Phragmites karka(Pi + Ph). Several water quality parameters including BOD in the effluent discharged from different constructed wetland microcosm units successfully meet the discharge criteria after three days of retention time. It was observed that both the UASB- and FAB-based reactors alone do not achieve water quality up to discharge standards. However, the available data shows that the performance of the UASB reactors in integration with constructed wetlands in terms of BOD removal reached the highest (up to 98%). Similarly, the removal of other parameters such as chemical oxygen demand (90%), total suspended solids (92%), total nitrogen (89%), NH4+–N (70%), and TP (88%) was also recorded as optimum. Consequently, the integration of constructed wetlands systems designed using Pistia stratiotesand Phragmites karkawith UASB-based reactors can significantly enhance the performance and may offer a viable integrated wastewater treatment technology.

Nutrient enrichment in lakes due to municipal wastewater discharge and agricultural run-off leads to excessive growth of algae and aquatic macrophytes leading to their altered trophic states. This paper presents the effect of wastewater-induced nutrient enrichment on the anatomical changes and elemental profiling in three common aquatic macrophytes of freshwater lakes in India’s Central Gangetic Plain. It is observed that with increase in trophic state, biomineral depositions are seen in the leaf anatomy of aquatic macrophytes. Elemental variations in free-floating (Eichhornia crassipes), submerged (Hydrilla verticillata) and emergent (Typha latifolia) macrophytes collected from three different lakes with different catchment characteristics and trophic state using EDS (Energy-Dispersive X-Ray Spectroscopy) spectra show that with increasing trophic state, elemental constituent in the aquatic macrophytes also increases. The rhizome of Eichhornia crassipesshowed the formation of calcium oxalate crystals in SEM (Scanning Electron Microscope) images and EDS analysis. Among macrophytes, floating and submerged macrophytes show a greater number of elemental constituents as compared to the emergent macrophytes. The findings of this study show that the anatomical and elemental responses of macrophytes are dependent both on the water quality and trophic state of the lakes. In-situ responses of macrophytes are based on their tolerance level against the pollution load and environmental changes. This study has important implications for understanding the response mechanism of macrophytes with changing water quality and increasing trophic state, which may help in proper management of freshwater ecosystem.

Structural changes in rabbit muscle pyruvate kinase (PK) induced by phosphoenolpyruvate (PEP) and Mg2+binding were studied by attenuated total reflection Fourier transform infrared spectroscopy in combination with a dialysis accessory. The experiments indicated a largely preserved secondary structure upon PEP and Mg2+binding but also revealed small backbone conformational changes of PK involving all types of secondary structure. To assess the effect of the protein environment on the bound PEP, we assigned and evaluated the infrared absorption bands of bound PEP. These were identified using 2,3-13C2-labeled PEP. We obtained the following assignments: 1589 cm−1(antisymmetric carboxylate stretching vibration); 1415 cm−1(symmetric carboxylate stretching vibration); 1214 cm−1(C-O stretching vibration); 1124 and 1110 cm−1(asymmetric PO32-stretching vibrations); and 967 cm−1(symmetric PO32-stretching vibration). The corresponding band positions in solution are 1567, 1407, 1229, 1107, and 974 cm−1. The differences for bound and free PEP indicate specific interactions between ligand and protein. Quantification of the interactions with the phosphate group indicated that the enzyme environment has little influence on the P-O bond strengths, and that the bridging P-O bond, which is broken in the catalytic reaction, is weakened by <3%. Thus, there is only little distortion toward a dissociative transition state of the phosphate transfer reaction when PEP binds to PK. Therefore, our results are in line with an associative transition state. Carboxylate absorption bands indicated a maximal shortening of the length of the shorter C-O bond by 1.3 pm. PEP bound to PK in the presence of the monovalent ion Na+exhibited the same band positions as in the presence of K+, indicating very similar interaction strengths between ligand and protein in both cases.

Direct shoot regeneration was achieved from immature inflorescence explants of Chlorophytum arundinaceum and C. borivilianum on half-strength Murashige & Skoog (MS) medium supplemented with 3.0 mg L−1 BA, 150 mg L−1 Ads, 0.1 mg L−1 NAA and 3% (w/v) sucrose under a 16-h photoperiod. The shoot buds developed within 2–3 weeks of culture. High frequency of shoot bud regeneration was achieved when cultured on similar medium in subsequent subcultures. The apex portion (Type I) of the inflorescence produced more shoot buds as compared to the middle ones (type II). More than 75% of the terminal segment explants produced shoot buds within 4-week of culture. Response of basal portion (Type III) was negative for shoot bud initiation. Shoots rooted on half-strength basal MS medium supplemented with half-strength MS medium, 0.1 mg L−1 IAA and 2% (w/v) sucrose. Micropropagated plantlets were hardened in the green house and successfully established in the soil where 90% of the plants survived. This protocol would be useful for commercial micropropagation and genetic improvement prograrmme.

Mobile robots have wide applications in challenging real-world scenarios. Therefore, it is necessary to have an advanced controller to control the robotic systems smoothly. An artificial bee colony optimization algorithm and recurrent neural network are combined to develop a hybrid controller and implemented for multi-robotic navigational problems in unknown static and dynamic environments. The designed controller is validated through MATLAB simulations coupled with real-time experiments. Results obtained via both the testing platforms are analysed, and found a good agreement between them as the deviation is less than 5.5%. Further, the developed controller is compared with existing controllers, and improvements of 20%, 10.19%, 13.53% is noted in terms of path length.

A person suspected of having Alzheimer’s disease (AD) is clinically diagnosed for the presence of principal biomarkers, especially misfolded amyloid-beta (Aβ) and tau proteins in the brain regions. Existing radiotracer diagnostic tools, such as PET imaging, are expensive and have limited availability for primary patient screening and pre-clinical animal studies. To change the status quo, small-molecular near-infrared (NIR) probes have been rapidly developed, which may serve as an inexpensive, handy imaging tool to comprehend the dynamics of pathogenic progression in AD and assess therapeutic efficacy in vivo. This Perspective summarizes the biochemistry of Aβ and tau proteins and then focuses on structurally diverse NIR probes with coverages of their spectroscopic properties, binding affinity toward Aβ and tau species, and theranostic effectiveness. With the summarized information and perspective discussions, we hope that this paper may serve as a guiding tool for designing novel in vivoimaging fluoroprobes with theranostic capabilities in the future.

• The requirement of dietary nucleotide sources for maximal helper T-cell function has been demonstrated. The effect of dietary nucleotide restriction was tested during two forms of nutritional stress: starvation and protein malnutrition. In the starvation model, mice were fed chow diet, nucleotide free or nucleotide free supplemented with 0.25% yeast RNA, for at least 4 weeks. The animals were then starved for 5 days, at which time they were killed and mitogen assays were performed using spleen cells. Animals previously maintained on the nucleotide-free diet supplemented with RNA showed a significant increase in spontaneous concanavalin A and phytohemagglutinin-stimulated blastogenesis. Protein malnutrition was induced by feeding Balb/c mice a protein-free diet for 7 to 10 days. These mice then received either the protein-free diet, the nucleotide-free diet, or the nucleotide-free diet supplemented with 0.25% yeast RNA. Popliteal lymph node assays were then performed. The chow diet, nucleotide-free diet, and nucleotide-free diet supplemented with 0.25% yeast RNA led to a restoration of body weight, but only the chow and supplemented diets restored significant popliteal lymph node immune reactivity. These studies using starvation and protein-malnutrition models clearly indicate the nutritional role of nucleotides in the maintenance and restoration of the immune response.(Arch Surg. 1990;125:86-90)

The kinetics of oxidation of ethanol by bromate ion in hydrochloric acid medium has been investigated. The reaction involves the formation of the intermediate bromate ester which is facilitated by the methyl group in ethanol but the electron attracting character (F>Cl>Br) of the halogens attached to the β-carbon of the alcohol makes the esterification more difficult.

The kinetics of oxidation of methanol by bromate ion in hydrochloric acid medium has been investigated. A mechanism consistent with the experimental observations is suggested.

Coal is the primary source of energy in almost every nation. As the energy demand is increasing, a greater amount of ash is generated as a result of increased coal consumption. The present study is aimed to investigate the physical, chemical and rheological properties of fly ash and its suspension with water for the design of a slurry transport system. The mineralogical composition of the fly ash shows large fraction silica and alumina. The rheological analysis shows that at lower concentrations (10-30%), the slurry behaves like a Newtonian fluid whereas it behaves like a non-newtonian fluid at higher concentrations (40-60%). The rheological characteristics can further used for the prediction of flow characteristics of the slurry in a horizontal pipe.

Temperature generation in cutting tools is one of the major causes of tool failure especially during hard machining where machining forces are quite high resulting in elevated temperatures. Thus, the present work investigates the temperature generation during hard machining of AISI 52100 steel (62 HRC hardness) with uncoated and PVD AlTiN coated Al2O3/TiCN mixed ceramic cutting tools. The experiments were performed on a heavy duty lathe machine with both coated and uncoated cutting tools under dry cutting environment. The temperature of the cutting zone was measured using an infrared thermometer and a finite element model has been adopted to predict the temperature distribution in cutting tools during machining for comparative assessment with the measured temperature. The experimental and numerical results revealed a significant reduction of cutting zone temperature during machining with PVD AlTiN coated cutting tools when compared to uncoated cutting tools during each experimental run. The main reason for decrease in temperature for AlTiN coated tools is the lower coefficient of friction offered by the coating material which allows the free flow of the chips on the rake surface when compared with uncoated cutting tools. Further, the superior wear behaviour of AlTiN coating resulted in reduction of cutting temperature.

The discovery of graphene showcased anability to isolate atomic thin sheet from layered graphite, and presented a precedent to the scientific community for exploring a similar possibility in other layered materials. Magnesium diboride (MgB2), which has metal atoms sandwiched in between boron honeycomb planes, represents an ionic layered material isostructural to intercalated graphite. We show that ultrasonication of MgB2 in ionic liquid (1-butyl-3-methyl imidazolium tetrafluoroborate)results in a stable dispersion of few-layer-thick boron based nanosheets. Furthermore, these nanosheets ([?]3-6 um wide, [?]2 nm thick) are found to exhibit an optical band-gap of [?]3.3eV alongwith excitation wavelength dependent photoluminescence.

Background, Aims, and Objectives. Congenital diaphragmatic hernia typically presents in childhood but in adults is extremely rare entity. Surgery is indicated for symptomatic and asymptomatic patients who are fit for surgery. It can be done by laparotomy, thoracotomy, thoracoscopy, or laparoscopy. With the advent of minimal access techniques, the open surgical repair for this hernia has decreased and results are comparable with early recovery and less hospital stay. The aim of this study is to establish that laparoscopic repair of congenital diaphragmatic hernia is a safe and effective modality of surgical treatment. Materials and Methods. A retrospective study of laparoscopic diaphragmatic hernia repair done during May 2011 to Oct 2014. Total n=13 (M/F: 11/2) cases of confirmed diaphragmatic hernia on CT scan, 4 cases Bochdalek hernia (BH), 8 cases of left eventration of the diaphragm (ED), and one case of right-sided eventration of the diaphragm (ED) were included in the study. Largest defect found on the left side was 15 × 6 cm and on the right side it was 15 × 8 cm. Stomach, small intestine, transverse colon, and omentum were contents in the hernial sac. The contents were reduced with harmonic scalpel and thin sacs were usually excised. The eventration was plicated and hernial orifices were repaired with interrupted horizontal mattress sutures buttressed by Teflon pieces. A composite mesh was fixed with nonabsorbable tackers. All patients had good postoperative recovery and went home early with normal follow-up and were followed up for 2 years. Conclusion. The laparoscopic repair is a safe and effective modality of surgical treatment for congenital diaphragmatic hernia in experienced hands.

A dialysis accessory for attenuated total reflection (ATR) infrared spectroscopy is described together with an evaluation based on known systems with well-studied infrared spectra, such as chemical oxidation and reduction of cytochrome c and substrate binding to the Ca2+-ATPase. Changes in the infrared spectra of the two proteins are successfully monitored with the dialysis accessory. The accessory was developed in our laboratory for the diamond 9-reflections SensIR ATR unit. It can be used to study absorbance changes of macromolecules which are induced by low molecular weight compounds, for example the binding of substrates, inhibitors or ions to macromolecules as well as effects of pH, ionic strength or denaturants on the structure of macromolecules. The dialysis accessory confines the macromolecule of interest to a sample compartment created between the ATR crystal and the dialysis membrane. On the other side of the dialysis membrane, a reservoir for the sample medium is created. In this way the low molecular weight compound of interest can exchange freely between the reservoir and the sample compartment via the dialysis membrane. This provides a flexible way to change sample conditions for the macromolecule of interest, allowing for example initiation of ligand binding.