Addressing the increasing demand for green additives in drilling fluids is essential for the sustainable development of the oil and gas industry. Fluid loss into porous and permeable formations during drilling presents significant challenges. This study introduced an innovative, environmentally sustainable drilling fluid known as nano-biodegradable drilling fluid (NBDF). The NBDF formulation incorporates greenly synthesized zinc nanorods (ZNRs) and gundelia seed shell powder, with ZNRs derived from Cydonia oblonga plant extracts using an eco-friendly method. The research developed multiple drilling fluid variants for experimentation: a reference drilling fluid (BM); biodegradable drilling fluid (BDF) with particle sizes of 75, 150, 300, and 600 µm at concentrations ranging from 0.5 to 1 wt% (GSMs); a drilling nanofluid (DNF) with ZNRs at a 0.1 wt% concentration (ZNR); and NBDF combining both nano and gundelia waste (GS-ZNR). Experimental tests were conducted under various temperature and pressure conditions, including low temperature and low pressure (LTLP) and high temperature and high pressure (HTHP). Rheological and filtration measurements were performed to assess the impact of the nano-biodegradable additives on flow behavior and fluid loss. Results indicated that incorporating 1 wt% of gundelia seed shell powder with a particle size of 75 µm led to a 19.61% reduction in fluid loss compared to BM at 75 °C and 200 psi. The performance of the same GSM improved by 31% under identical conditions when 1 wt% of zinc ZNRs was added. Notably, the GS-ZNR formulation demonstrated the most effective performance in reducing fluid loss into the formation, decreasing mud cake thickness, and enhancing the flow behavior of the non-Newtonian reference drilling fluid. This study highlights the relevance of particle size in the effectiveness of biodegradable additives and underscores the potential of NBDF to address environmental concerns in the oil and gas drilling industry.

The application of cellulose derivatives including carboxymethyl cellulose (CMC), polyanionic cellulose (PAC), hydroxyethyl cellulose (HEC), cellulose nanofibrils (CNFs), and cellulose nanocrystals (CNCs) has gained enormous interest, especially as environmentally friendly additives for water-based drilling fluids (WBDFs). This is due to their sustainable, biodegradable, and biocompatible nature. Furthermore, cellulose nanomaterials (CNMs), which include both CNFs and CNCs, possess unique properties such as nanoscale dimensions, a large surface area, as well as unique mechanical, thermal, and rheological performance that makes them stand out as compared to other additives used in WBDFs. The high surface hydration capacity, strong interaction with bentonite, and the presence of a complex network within the structure of CNMs enable them to act as efficient rheological modifiers in WBDFs. Moreover, the nano-size dimension and facilely tunable surface chemistry of CNMs make them suitable as effective fluid loss reducers as well as shale inhibitors as they have the ability to penetrate, absorb, and plug the nanopores within the exposed formation and prevent further penetration of water into the formation. This review provides an overview of recent progress in the application of cellulose derivatives, including CMC, PAC, HEC, CNFs, and CNCs, as additives in WBDFs. It begins with a discussion of the structure and synthesis of cellulose derivatives, followed by their specific application as rheological, fluid loss reducer, and shale inhibition additives in WBDFs. Finally, the challenges and future perspectives are outlined to guide further research and development in the effective utilization of cellulose derivatives as additives in WBDFs.

Drilling through shale formations can be expensive and time-consuming due to the instability of the wellbore. Further, there is a need to develop inhibitors that are environmentally friendly. Our study discovered a cost-effective solution to this problem using Gum Arabic (ArG). We evaluated the inhibition potential of an ArG clay swelling inhibitor and fluid loss controller in water-based mud (WBM) by conducting a linear swelling test, capillary suction timer test, and zeta potential, fluid loss, and rheology tests. Our results displayed a significant reduction in linear swelling of bentonite clay (Na-Ben) by up to 36.1% at a concentration of 1.0 wt. % ArG. The capillary suction timer (CST) showed that capillary suction time also increased with the increase in the concentration of ArG, which indicates the fluid-loss-controlling potential of ArG. Adding ArG to the drilling mud prominently decreased fluid loss by up to 50%. Further, ArG reduced the shear stresses of the base mud, showing its inhibition and friction-reducing effect. These findings suggest that ArG is a strong candidate for an alternate green swelling inhibitor and fluid loss controller in WBM. Introducing this new green additive could significantly reduce non-productive time and costs associated with wellbore instability while drilling. Further, a dynamic linear swelling model, based on machine learning (ML), was created to forecast the linear swelling capacity of clay samples treated with ArG. The ML model proposed demonstrates exceptional accuracy (R2 score = 0.998 on testing) in predicting the swelling properties of ArG in drilling mud.

In this study, the reservoir drill-in fluid (RDF) was modified and optimized to improve the rheological properties and reduce the filtration properties of the drilling fluid used for drilling the oil-bearing zone horizontally. In polymer science, degradation generally refers to a complex process, by which a polymeric material exposed to the environment and workload loses its original properties. Degradation is usually an unwanted process. In certain cases, however, controlled polymer degradation is useful. For instance, it can improve the processability of the polymer or can be used in recycling or natural decomposition of waste polymer. Thus, the drilling fluid and parameter data of 30 horizontal wells that were drilled in the south of Iraq were collected using several reservoir drill-in fluids (RDFs), including FLOPRO, salt polymer mud (SPM), non-damaged fluid (NDF), and FLOPRO_PTS-200 (including the polymer thermal stabilizer). The obtained results showed that the polymer temperature stabilizer (PTS-200) enabled reducing the filtration rate by 44.33% and improved the rheological properties by 19.31% as compared with FLOPRO. Additionally, the average cost of NDF and SPM drilling fluids for drilling the horizontal section of the selected wells is around USD 96,000 and USD 91,000, respectively. However, FLOPRO-based drilling fluid showed less cost for drilling the horizontal section, which is USD 45,000.

UNASSIGNED: Fluid loss due to diarrhea remains a significant cause of mortality among children under the age of 5.
UNASSIGNED: Oral rehydration therapy (ORT) is a first-line therapeutic measure to compensate the volume loss due to diarrhea and vomiting among gastroenteritis patients. Despite adequate knowledge, the practice of ORT is limited, particularly in developing countries.
UNASSIGNED: Several recommendations are provided regarding the use of ORT to treat hypovolemia, however, the information regarding its adequate usage is restricted within the healthcare centers and professionals.
UNASSIGNED: This review highlights the importance of providing recommendations regarding the use of ORT. We also discuss the barriers and alternatives that might limit its use.

Adequate fluid replacement during exercise is an important consideration for athletes, however sweat rate (SR) can vary day-to-day. The purpose of this study was to investigate day-to-day variations in SR while performing self-selected exercise sessions to evaluate error in SR estimations in similar temperature conditions. Thirteen endurance-trained athletes completed training sessions in a case-series design 1x/week for a minimum 30 min of running/biking over 24 weeks. Body mass was recorded pre/post-training and corrected for fluid consumption. Data were split into three Wet-Bulb Globe Thermometer (WBGT) conditions: LOW (<10 °C), MOD (10-19.9 °C), HIGH (>20 °C). No significant differences existed in exercise duration, distance, pace, or WBGT for any group (p > 0.07). Significant differences in SR variability occurred for all groups, with average differences of: LOW = 0.15 L/h; MOD = 0.14 L/h; HIGH = 0.16 L/h (p < 0.05). There were no significant differences in mean SR between LOW-MOD (p > 0.9), but significant differences between LOW-HIGH and MOD-HIGH (p < 0.03). The assessment of SR can provide useful data for determining hydration strategies. The significant differences in SR within each temperature range indicates a single assessment may not accurately represent an individual\'s typical SR even in similar environmental conditions.

Nanocomposite materials have distinctive potential for various types of captivating usage in drilling fluids as a well-designed solution for the petroleum industry. Owing to the improvement of drilling fluids, it is of great importance to fabricate unique nanocomposites and advance their functionalities for amplification in base fluids. There is a rising interest in assembling nanocomposites for the progress of rheological and filtration properties. A series of drilling fluid formulations have been reported for graphene-derived nanocomposites as additives. Over the years, the emergence of these graphene-derived nanocomposites has been employed as a paradigm to formulate water-based drilling fluids (WBDF). Herein, we provide an overview of nanocomposites evolution as engineered materials for enhanced rheological attributes in drilling operations. We also demonstrate the state-of-the-art potential graphene-derived nanocomposites for enriched rheology and other significant properties in WBDF. This review could conceivably deliver the inspiration and pathways to produce novel fabrication of nanocomposites and the production of other graphenaceous materials grafted nanocomposites for the variety of drilling fluids.

Motor-racing drivers are often exposed to hot environments and may be susceptible to fluid loss and hydration issues, which could influence driving performance. This study assessed the effect of dehydration and heat stress on performance during a short, simulated motor-racing task. Nine healthy males (age: 26.6 ± 7.5 y, body mass: 78.8 ± 12.5 kg, mean ± SD) completed two passive dehydration (sauna) procedures (targeting -1% and -3% body mass loss (BML)) on separate occasions. Driving performance was assessed pre-dehydration (Baseline), immediately post-dehydration (Hot) and following a cooling period (Cool). Measures of driving performance included lap time and sector-time for one section of the track. Subjective ratings of mood, thermal stress and comfort were also collected during trials. Mean lap times were not different between Baseline, Hot, Cool conditions for both 1% (68.44 ± 1.43 s, 68.06 ± 1.17 s, 68.23 ± 1.25 s) and 3% (68.33 ± 1.68 s, 68.01 ± 1.15 s, 68.06 ± 1.26 s) trials respectively. In addition, mean sector times were not different between Baseline, Hot, Cool conditions for both 1% (11.61 ± 0.28 s, 11.55 ± 0.45 s, 11.59 ± 0.35 s) and 3% (11.49 ± 0.33 s, 11.56 ± 0.33 s, 11.63 ± 0.71 s) trials respectively. Changes in participants\' subjective ratings (i.e. decreased alertness, concentration and comfort; increased tiredness and light-headedness) were observed at both levels of dehydration (1% and 3% BML), irrespective of heat stress. Thus, fluid loss and heat stress are unlikely to affect driver\'s motor-racing performance during short duration events. However, the impact of dehydration and heat stress on tasks of longer duration that accurately represent the demands associated with motor-racing requires further consideration.

OBJECTIVE: Skin tattoos have been shown to reduce localised sweat rate and increase sweat sodium concentration ([Na+]) when sweating is artificially stimulated. This study investigated whether similar responses are observed with exercise-induced sweating.
METHODS: Unblinded, within-participant control, single trial.
METHODS: Twenty-two healthy individuals (25.1±4.8 y (Mean±SD), 14 males) with a unilateral tattoo ≥11.4cm2 in size, ≥2 months in age, and shaded ≥50% participated in this investigation. Participants undertook 20min of intermittent cycling (4×5min intervals) on a stationary ergometer in a controlled environment (24.6±1.1°C; 64±6% RH). Resultant sweat was collected into absorbent patches applied at two pairs of contralateral skin sites (pair 1: Tattoo vs. Non-Tattoo; pair 2: Control 1 vs. Control 2 (both non-tattooed)), for determination of sweat rate and sweat [Na+]. Paired samples t-tests were used to determine differences between contralateral sites.
RESULTS: Tattoo vs. Non-Tattoo: Neither sweat rate (Mean±SD: 0.92±0.37 vs. 0.94±0.43mg·cm-2·min-1, respectively; p=0.693) nor sweat [Na+] (Median(IQR): 37(32-52) vs. 37(31-45) mM·L-1, respectively; p=0.827) differed. Control 1 vs. Control 2: Neither sweat rate (Mean±SD: 1.19±0.53 vs. 1.19±0.53mg·cm-2·min-1, respectively; p=0.917) nor sweat [Na+] (Median(IQR): 29(26-41) vs. 31(25-43)mM·L-1, respectively; p=0.147) differed. The non-significant differences for sweat rate and [Na+] between Tattoo vs. Non-Tattoo were inside the range of the within participant variability (sweat rate CVi=5.4%; sweat [Na+] CVi=4.4%).
CONCLUSIONS: Skin tattoos do not appear to alter the rate or [Na+] of exercise-induced sweating. The influence of skin tattoos on localised sweat responses may have previously been over-estimated.

Data presented in this article focused on the application of Methyl Ester Sulphonate (MES) surfactant and nanopolystyrene in water based drilling fluid. Data from rheology study using Bingham and Power law models showed that the synergy of MES and nanopolystyrene improved the formulated drilling fluid. Filtration study under LPLT and HPHT conditions showed that MES and nanopolystyrene drilling fluid reduced filtration loss by 50.7% at LPLT and 61.1% at HPHT conditions. These filtration data were validated by filter cake permeability and scanning electron microscope images.