Laboratory Experiments Research Articles

Qualifying and quantifying the different ways in which people are annoyed by aircraft noise

Aircraft noise remains a major problem for many people living near airports, despite the efforts of the various air traffic operators and aircraft manufacturers to reduce the nuisance. Noise abatement usually relies on quantitative approaches based on noise measurements at source or in residential areas. However, field studies have shown that the level of annoyance experienced within a given noise exposure zone varies widely, demonstrating that noise levels alone do not explain the experience of local residents. The present work brought together a wide range of disciplines (aeronautics, acoustics, linguistics, psychoacoustics, social and environmental psychology) to define a common framework for reconciling field and laboratory studies on aircraft noise annoyance. A survey of 1250 people living near airports enabled us to precisely qualify the annoyance experienced, and to identify 6 highly differentiated annoyance profiles based on non-acoustic factors. Focus groups and laboratory experiments with people living near airports revealed an impact of annoyance profiles on both qualitative and quantitative evaluation of noise annoyance, which confirms the diversity of their experiences in the same listening situation.

Instrumentation techniques for the measurement of gunfire (Part 3)

This paper is the third in a series concerning near-field measurement of sound pressure from small arms gunfire. It has been long established that exposure to gunfire events can lead to permanent threshold shift for an unprotected shooter. Close to a shooter's ear, the peak sound pressure level from a rifle or pistol can be 155-to-160 decibels with a pulse rise time on the order of ten microseconds. The U.S. Department of Defense has considered two approaches for assessing exposure limits from small arms gunfire - one involves the unweighted peak sound pressure and the other a series of A-weighted sound exposure events integrated to obtain an equivalent eight-hour dose. This dose is then compared to hearing damage risk criteria established for continuous noise signals. The first approach places great demands on the measurement system since the necessary bandwidth extends well into the ultrasonic range, thereby requiring fast slewing from the amplifiers combined with high sampling rates from the digitizer. The second approach requires the A-weighting filter to have specified time and frequency domain properties in the ultrasonic region. The paper discusses some laboratory experiments using actual gunfire signals to simulate the outcome from both approaches.

Flyover auralization of a blended wing body aircraft considering atmospheric turbulence effects

In the ARTEM project a novel blended wing body (BWB) long-range aircraft was designed and optimized for low-noise operation. Virtual flyovers of different BWB vehicle variants were synthesized and auralized in the AuraLab using a loudspeaker array. Prior to auralizing the novel aircraft, the applied methods were hierarchically validated by comparison with field recordings of existing jet aircraft, assessing acoustical indices, time-frequency features, perceived plausibility, and induced noise annoyance. To achieve convincing syntheses, the focus was on developing new auralization models for a realistic representation of atmospheric turbulence effects. The syntheses of the BWB obtained with the successfully validated methods were then used in psychoacoustic laboratory experiments for perception-based evaluation regarding (minimized) noise annoyance. The evaluation revealed that, while the BWB may initially be perceived as somewhat more unfamiliar, it is substantially less annoying than current tube-and-wing long-range aircraft of similar range and mission for take-offs as well as for landings.

A synthesized airless tyre traffic sound scenario for health impact assessment

Within the LEON-T project, a composite wheel is being developed that is aimed to reduce noise from the tyre-road interaction by removing the air filled cavity entirely and by allowing the tread belt be permeable, thus reducing air pressure build-up in the contact patch. Parallel to the developement of the composite "airless tyre" the potential health impact from reducing noise by adopting such a composite wheel has been investigated by synthesizing the sound of a composite wheel. The synthesized sound has then been used to create different traffic flow scenarios used for laboratory studies of effects on sleep from noise. Results indicate positive effects on health through less sleep disturbance from composite wheel noise as compared to ordinary tyre noise. This paper describes the synthesis process and the scenarios used for the sleep laboratory experiments.

Accuracy of fish-eye camera device for aircraft positioning based on laboratory experiment combining computer graphic and 3D Projection

For the management of airborne mobility devices such as airplanes and UAVs, such as noise assessment, it is important to measure the three-dimensional position of the aircraft, and various technologies have been researched and developed. We have developed an Aircraft Positioning Camera (APC) based on an IoT device equipped with a fisheye camera that can mechanically measure aircraft position at a local area with low cost and with high mobility. The performance of this APC is still uncertain as to the limits of the flight altitude and speed of the aircraft that can be measured. Therefore, a detailed study of its performance is needed. Since, it is difficult to standardize the conditions such as weather and ground surface conditions, it is effective to conduct these studies in a laboratory where environmental changes can be controlled. The performance of this APC was examined at an experimental facility where images captured by a 360-degree camera or computer graphics can be projected in three dimensions onto a hemispherical dome.

Exposure of employees to very high frequencies: laboratory measurements

Many occupational sectors are subject to noise exposure to very high audible frequencies (VHF) or low frequency ultrasound (LFUS): welding, food cutting, cleaning, etc. Although studies on employee exposure to these sound sources have been carried out since the 1960s, the question of the location of the measuring microphone and the representativeness of the measurement remains. As part of a study focusing on the risks associated with exposure to VHF/LFUS, the INRS conducted laboratory experiments on a mannequin to assess the variability of exposure measurements under controlled conditions as a function of microphone location (shoulder, ear entrance, etc.), source frequency and source position in azimuth. Of particular interest was the appropriateness of positioning the microphone at temple level via a dedicated mounting system suitable for use in the field. The findings of this preliminary work will be used to develop a protocol for measuring VHF/LFUS exposure in situ.

Active noise-cancelling headphones do not improve cognitive performance in office noise environment

Our purpose was to determine the influence of different use settings of on-ear ANC (active noise-cancelling) headphones on performance, experience, and physiological stress in conditions resembling an office where task irrelevant speech is present. Laboratory experiment involved 54 participants, who were exposed to five conditions: 1. No headphones, 2. Headphones without ANC operation, 3. Headphones with ANC operation, 4. Headphones with sound masking playback, 5. Headphones with ANC operation and sound masking playback. In all conditions, speech was present in the room at 52 dB LAeq. Masking was 51 dB LAeq wideband noise played from the headphones. Participants' performance was measured with visual serial recall and 3-back tasks, and physiological stress with heart rate variability. The condition did not influence performances nor physiological stress. The only effects of sound condition were observed in subjective experiences. With masking (conditions 4 and 5), the speech was less annoying than without the headphones (condition 1). Sound environment was estimated to impair performance and disturb concentration less than without the headphones only in condition 5. Therefore, using headphones together with masking and ANC function can improve experience. Using headphones with ANC function alone did not improve performance nor reduce stress level.

Identification and field verification of the aggregation pheromone components produced by male Holotrichia parallela Motschulsky (Coleoptera: Scarabaeidae).

The chafer beetle, Holotrichia parallela, causes damage to numerous economically significant crops worldwide. Adult beetles exhibit aggregation behavior likely mediated by a male-produced pheromone. Advancements in biological research technology have facilitated the identification of insect aggregation pheromones and promoted their applications as bait for trapping and monitoring pests. Currently, only a few active components of aggregation pheromones from Holotrichia species have been identified. However, the specific components of aggregation pheromones produced by H. parallela remain unknown. In this study, we initially observed from Y-tube olfactometer assays that both male and female H. parallela were significantly attracted to volatiles emitted by males, but not to those from females. We then collected hindgut crude extracts of male adults and carried out gas chromatography-mass spectrometry analysis to identify potential aggregation pheromone components. Pentadecyl acetate, cis-13-docosenol, and behenic acid were identified as male-specific compounds in comparison to female extracts, serving as components of the aggregation pheromone in H. parallela. We further evaluated their attractiveness to H. parallea in both laboratory and field experiments. In laboratory settings, pentadecyl acetate, cis-13-docosenol, and behenic acid evoked significant responses to both males and females at specific concentrations, as evidenced by both electroantennography tests and behavioral bioassays. Under field conditions, traps baited with these three compounds captured significantly more H. parallela adults compared to control traps. In this study, we found that pentadecyl acetate, cis-13-docosenol, and behenic acid are specifically present in male H. parallela, serving as aggregation pheromones. Both laboratory and field-trapping experiments suggest their potential as monitoring and controlling tools against H. parallela adults. © 2024 Society of Chemical Industry.

Enhancing appeal of aggregate payment framing: effects of temporal payment framing and goal proximity on consumer purchase decisions

Purpose The purpose of this paper is to examine how temporal payment framing (i.e. segregate vs aggregate framing) and goal proximity (i.e. proximal vs distal goals) influence consumer purchase decisions. Design/methodology/approach Study 1 included four laboratory experiments and examined the moderating role of goal proximity in temporal payment framing. Study 2, using Facebook and a firm’s website for an online field experiment with a data set of 38,731 impressions, extended Study 1, enhancing the generalizability of the findings. Findings Consumers exhibited a stronger purchase intention for segregate payment framing. This effect became less pronounced when goal proximity was coupled with temporal payment framing. If products or services emphasized a distal goal, individuals showed greater responses for aggregate payment framing rather than segregate payment framing. The effect was substantial, demonstrating a consistent behavioral pattern in individuals’ browsing choices, including browsing duration and the number of pages viewed. Research limitations/implications Future studies ought to investigate if the alignment of goal proximity and temporal payment framing holds consistent across different product types, such as utilitarian versus hedonic products, or search goods versus experience goods. Practical implications Marketers can improve the effectiveness and efficiency of their marketing strategies by crafting persuasive messages where the monetary offer is in harmony with the goal proximity. Originality/value Temporal payment framing literature has focused on payment framing; however, consumers make their decisions based on a combination of factors rather than solely on payment framing. This study identifies the moderating role of goal proximity.

The spatial Whitham equation

The Whitham equation is a non-local, nonlinear partial differential equation that models the temporal evolution of spatial profiles of surface displacement of water waves. However, many laboratory and field measurements record time series at fixed spatial locations. To directly model data of this type, it is desirable to have equations that model the spatial evolution of time series. The spatial Whitham (sWhitham) equation, proposed as the spatial generalization of the Whitham equation, fills this need. In this paper, we study this equation and apply it to water-wave experiments on shallow and deep water. We compute periodic travelling-wave solutions to the sWhitham equation and examine their properties, including their stability. Results for small-amplitude solutions align with known results for the Whitham equation. This suggests that the systems are consistent in the weakly nonlinear regime. At larger amplitudes, there are some discrepancies. Notably, the sWhitham equation does not appear to admit cusped solutions of maximal wave height. In the second part, we compare predictions from the temporal and spatial Korteweg–de Vries and Whitham equations with measurements from laboratory experiments. We show that the sWhitham equation accurately models measurements of tsunami-like waves of depression, waves of elevation, and solitary waves on shallow water. Its predictions also compare favourably with experimental measurements of waves of depression and elevation on deep water. Accuracy is increased by adding a phenomenological damping term. Finally, we show that neither the sWhitham nor the temporal Whitham equation accurately models the evolution of wave packets on deep water.

Impact of death-related media information on the effectiveness of in-feed advertising: A compensatory consumption perspective

With the increasing availability of news related to unexpected and catastrophic events, such as public health issues, natural disasters, murder cases, and terrorist attacks, the coexistence of death-related media information and commercial advertising has become prevalent in media platforms. This study is to clarify whether, when, and why death-related media information impacts the effectiveness of in-feed advertising. We conducted a field study along with three laboratory experiments. Results indicated that users are more likely to click in-feed advertising when it was exposed to death-related information compared to information unrelated to death. Moreover, this positive effect would be amplified when the ads framing is loss (vs. gain) or the ads image brightness is high (vs. low). The findings not only enrich literature on death-related information but also contributes to practice regarding how to improve the effectiveness of in-feed advertising.

Thiosulfate leaching in carbonaceous gold-bearing ores in Ethiopia

One of the main unit operations in metallurgical processing plant designs is gold leaching. The traditional cyanidation process was chosen and is currently in widespread use. However, the mining sector is looking for lixiviants other than cyanide. Cyanide’s effects on the environment have made it difficult for humans and other biotic creatures to survive. There is now research to discover a substitute for this cyanide. It is currently argued that thiosulfate is a preferable substitute for cyanide. The effectiveness of thiosulfate as a leaching agent in carbonaceous gold-bearing ores in Ethiopia is discussed in this paper compared to cyanide. The study has looked into the advantages of employing thiosulfate over cyanide from a technical, and economic standpoint. The leaching effects of both lixiviants on carbonaceous gold-bearing ores extracted from MIDROC Legadembi Open Pit mine in Southern Ethiopia, Oromia region, were examined in a laboratory experiment. After 48 h of leaching, it was discovered that thiosulfate has a better and quicker recovery of 91.54% over 61.70% of cyanide recovery. Tables and graphs are used to demonstrate thiosulfate’s technical advantage over cyanide. As a result, this paper provides evidence regarding the Legadembi gold mine in Ethiopia’s amenability to thiosulfate leaching on carbonaceous gold-bearing ores. A further research perspective is also sought for thiosulfate leaching in other refractory ores.

Evaluating the impact of industrial wastes on the compressive strength of concrete using closed-form machine learning algorithms

Industrial wastes have found great use in the built environment due to the role they play in the sustainable infrastructure development especially in green concrete production. In this research investigation, the impact of wastes from the industry on the compressive strength of concrete incorporating fly ash (FA) and silica fume (SF) as additional components alongside traditional concrete mixes has been studied through the application of machine learning (ML). A green concrete database comprising 330 concrete mix data points has been collected and modelled to estimate the unconfined compressive strength behaviour. Considering the concerning environmental ramifications associated with concrete production and its utilization in construction activities, there is a pressing need to perform predictive model exercise. Furthermore, given the prevalent reliance of concrete production professionals on laboratory experiments, it is imperative to propose smart equations aimed at diminishing this dependency. These equations should be applicable for use in the design, construction, and performance assessment of concrete infrastructure, thereby reflecting the multi-objective nature of this research endeavour. It has been proposed by previous research works that the addition of FA and SF in concrete has a reduction impact on the environmental influence indicators due to reduced cement use. The artificial neural network (ANN) and the M5P models were applied in this exercise to predict the compressive strength of FA- and SF-mixed concrete also considering the impact of water reducing agent in the concrete. A sensitivity analysis was also conducted to determine the impact of the concrete components on the strength of the concrete. At the end, closed-form equations were proposed by the ANN and M5P with performance indices which outperformed previous models conducted on the same database size. The result of the sensitivity analysis showed that FA is most impactful of all the studied components thereby emphasizing the importance of adding industrial wastes in concrete production for improved mechanical properties and reduced carbon footprint in the concrete construction activities. Also, the M5P and ANN models with R2 of 0.99 showed a potential for use as decisive models to predict the compressive strength of FA- and SF-mixed concrete.

Advancing Nanopulsed Plasma Bubbles for the Degradation of Organic Pollutants in Water: From Lab to Pilot Scale

The transition from lab-scale studies to pilot-scale applications is a critical step in advancing water remediation technologies. While laboratory experiments provide valuable insights into the underlying mechanisms and method effectiveness, pilot-scale studies are essential for evaluating their practical feasibility and scalability. This progression addresses challenges related to operational conditions, effectiveness and energy requirements in real-world scenarios. In this study, the potential of nanopulsed plasma bubbles, when scaled up from a lab environment, was explored by investigating critical experimental parameters, such as plasma gas, pulse voltage, and pulse repetition rate, while also analyzing plasma-treated water composition. To validate the broad effectiveness of this method, various classes of highly toxic organic pollutants were examined in terms of pollutant degradation efficiency and energy requirements. The pilot-scale plasma bubble reactor generated a high concentration of short-lived reactive species with minimal production of long-lived species. Additionally, successful degradation of all pollutants was achieved in both lab- and pilot-scale setups, with even lower electrical energy-per-order (EEO) values at the pilot scale, 2–3 orders of magnitude lower compared to other advanced oxidation processes. This study aimed to bridge the gap between lab-scale plasma bubbles and upscaled systems, supporting the rapid, effective, and energy-efficient destruction of organic pollutants in water.

Zwitterionic MOF-embedded alginate beads with polydopamine surface functionalization for efficient doxycycline removal: Optimization and mechanistic study

The adsorptive removal of amphoteric antibiotics like doxycycline (DOX) is a difficult task because of the electrostatic repulsion between these amphoteric molecules and adsorbents. For this purpose, a zwitter adsorbent was fabricated by incorporating zwitter ZIF-67/MIL-88A binary MOF into the matrix of alginate (Alg); in addition, the surface of the beads was modified by polydopamine (PDA). The batch experiments implied the super-high adsorption efficacy of ZIF-67/MIL-88A@Alg@PDA toward DOX attained 384.61 ± 5.08 mg/g at a neutral pH medium, 25 °C, and using 0.02 g. The isotherm analysis implied the physisorption of DOX onto ZIF-67/MIL-88A@Alg@PDA, while the kinetic analysis denoted the chemisorption of DOX. The results of XPS, Zeta potential, and Lab experiments identified the types of physical and chemical interactions between ZIF-67/MIL-88A@Alg@PDA and DOX. The durability of the ZIF-67/MIL-88A@Alg@PDA beads was inspected by the recycling test, clarifying that the DOX adsorption aptitude declined by 12.22 mg/g. In addition, the measured leaching concentrations of cobalt and iron from leaching test were 0.008 and 0.098 mg/L. The ionic strength of ZIF-67/MIL-88A@Alg@PDA, implying an enhancement in the DOX removal (%) from 83.51 to 93.50 % by raising the NaCl concentration from 0.2 to 1.0 mol/L. Therefore, our study could provide a simple procedure to overcome the electrostatic repulsion that retard the adsorption process of the amphoteric drugs onto charged adsorbents with positive or negative charges. Additionally, this procedure could also generate an electrostatic interaction between the zwitter adsorbents and the amphoteric drugs at specific pH media when they are in a zwitterionic nature.

Magnesium geochemistry of authigenic carbonate at marine cold seep

Cold seeps, featured by their extremely methane-rich sedimentary environments, play a significant role in the geological history and are common in marine sediments across the seafloor. Primary dolomite, possibly mediated by microorganisms, can be widely discovered in methane-rich environments. Hence, cold seeps may provide new insights into the ‘dolomite problem’, which has confused geologists for decades. Magnesium isotope geochemistry of seep carbonates contributes to the understanding of the dolomite formation mechanism in marine environments. In this paper, magnesium geochemical characteristics of carbonates in modern sediments are summarized, along with rare researches on magnesium isotopes of seep carbonates. Methane vigorously interacts with sulfate by anaerobic oxidation of methane at cold seeps, producing vast amounts of dissolved sulfide which can significantly promote dolomitization of seep carbonates. Compared with temperature, alkalinity, mineralogy, etc., the competition between rapid carbonate precipitation rates and aqueous ligands may be the main factor of the magnesium fractionation at cold seeps, which is controlled by the kinetic effect. The range of magnesium isotopes of seep carbonates is narrow (from -3.46‰ to -2.36‰), and an upper limit of magnesium content seems to exist. This characteristic may be a good indicator for identifying dolomitization related to anaerobic oxidation of methane. Whereas, mechanisms of magnesium isotope fractionation and dolomitization at cold seeps remain unclear, necessitating more natural samples tested, stimulated calculation and laboratory experiment.

Experimental Study on the Impact of Sorption-Desorption on Nitrate Isotopes

Nitrate pollution is a global environmental problem, and mean nitrate levels have risen by an estimated 36% in global waterways since 1990. Tracing nitrate sources is important for water quality management, and nitrate isotopes (δ15N-NO3− and δ18O-NO3−) are commonly used for this purpose because of the different isotopic compositions of different sources. However, the impact of nitrate sorption on matrix and desorption from matrix on N and O isotopic composition of nitrate in liquid phase has not been well clarified. To explore the mechanism for the changes in nitrate concentration and isotopes in liquid phase during sorption and desorption, this study took a shale sample (enriched in clay minerals and commonly exposed in the Earth), conducted a series of laboratory experiments for nitrate sorption and desorption, and studied the impact of sorption and desorption on nitrate N and O isotopic composition in liquid phase. The results showed that the shale sample exhibited a rapid sorption and desorption rate for nitrate in the surface water samples, with the nitrate concentration in the solution decreasing from 14.3 mg/L to 4.1 mg/L within 5 min. The sorption data fit the Langmuir model better than that of the Freundlich model. The maximum possible sorption (Qmax) for the shale sample was estimated to be 46 μg/g. Preliminary laboratory experiments showed that changes in δ15N-NO3− values were not obvious, and changes in δ18O-NO3− values in liquid phase were minor during sorption and desorption of the shale sample, suggesting that nitrogen isotopic fractionation can be neglected, and the sorption of nitrate by the shale sample has a very limited impact on the distribution of nitrate isotopes in liquid phase. However, the impact of nitrate desorption on the nitrate isotopes in liquid phase depends on the isotopic composition of exchangeable nitrate in the solid phase, which may be related to antecedent water–rock interactions. This study provides important information for elucidating the evolution mechanism of nitrate and its isotopic compositions following sorption-desorption, and is conducive to revealing the nitrogen cycle law in the environment.

Quantification and mapping of regulating ecosystem services in canola agroecosystems (case study: Gorgan County, Iran).

Regulating services are the advantages that humans receive from regulating ecosystem processes. These services include, but are not limited to pollination, climate regulation, water purification, carbon sequestration, and erosion control. Quantifying and mapping ecosystem services in agroecosystems is one of the main effective actions to increase pay attention to these services and adopt suitable approaches to direct sustainability. The purpose of the study was quantification, and mapping of regulating ecosystem services in canola agroecosystems of Gorgan County, north of Iran. For this purpose, some regulating services such as carbon sequestration, climate regulation, soil microbial respiration, soil aggregate stability, and pollination by insects were evaluated based on the Common International Classification of Ecosystem Services framework. The information and data required for each of these services were collected through field measurements, laboratory experiments, and field surveys. After quantifying, the surveyed services in canola agroecosystems were presented on geospatial maps generated by ArcGIS software, version 10.3. Results showed that agroecosystems in the west and north of the studied region provided the more regulating services. Also, the results of the pollination showed that pollinating insects belonged to four orders and 13 families. The majority of the pollinators were Hymenoptera (44.74%), especially honey bees (Apis mellifera L.), Diptera (5.26%), Butterflies (Lepidoptera; 25%), and the beetles (Coleoptera; 25%), and Anthophora sp. and Andrena sp. were the second and the third most abundant pollinating species after honey bees. Generally, the canola agroecosystems close to the rivers and the natural ecosystems provided more services than other regions.

Laboratory assessment of predation and fecundity of Laricobius species (Coleoptera: Derodontidae), predators of hemlock woolly adelgid

ABSTRACT The hemlock woolly adelgid (HWA), Adelges tsugae (Hemiptera: Adelgidae), is native to the Pacific Northwest and Asia and is an invasive insect in the eastern United States causing widespread decline in health and increased mortality of native eastern and Carolina hemlock. Laboratory experiments conducted at ambient field temperatures were done to determine the adult and larval feeding totals on HWA and fecundity of the introduced predators Laricobius nigrinus and L. osakensis, and the native L. rubidus (Coleoptera: Derodontidae). During the 22-week period when Laricobius spp. adults are active in Virginia, from early November until late March the total mean ( x ¯ ± SE) of HWA eggs, nymphs, and adults were projected to be consumed per L. nigrinus (33.8 ± 4.0), L. osakensis (33.2 ± 4.0), and L. rubidus (16.4 ± 2.5) adults. Laricobius osakensis (102.1 ± 13.7) and L. nigrinus (72.0 ± 10.5), oviposited a similar number of eggs while L. rubidus (24.5 ± 5.2) oviposited a lower number of eggs. Mean larval consumption of HWA progrediens eggs was: L. nigrinus (169.6 ± 7.1), L. osakensis (140.1 ± 8.7), and L. rubidus (135.8 ± 12.8). The mean egg production of HWA was 74.5 ± 2.2. Based on predation and fecundity totals, L. osakensis was predicted to have a greater impact in reducing the number of HWA progrediens eggs than L. nigrinus and L. rubidus.

Influence of water on crystallographic preferred orientation patterns in a naturally deformed quartzite

Abstract. Laboratory experiments demonstrate that intragranular water exerts an important control on deformation within quartz, causing weakening and promoting plasticity. The role of water in natural quartz deformation, however, remains unclear, as recent studies find an inverse relationship between water content and the magnitude of plastic strain. Furthermore, little work has investigated the effects, if any, of water on the relative activity of various slip systems in quartz. We focus on a naturally strained quartzite from the Antietam Formation of the Blue Ridge in Virginia, USA. Quartz water content ranges from < 50 to > 2000 ppm H2O. Water content and crystallographic data were correlated for 968 grains, enabling us to explore the relationship between water content and quartz crystallographic preferred orientation (CPO) patterns. “Dry” (< 150 ppm H2O) and “wet” (> 500 ppm H2O) subsets show distinct CPOs; c axes of dry grains define a cross girdle oriented perpendicular to the extension direction (x), whereas c axes of wet grains are concentrated along the perimeter of the pole figure. All water content subsets show grains clustered near the direction of maximum shortening (z), consistent with activity of the basal 〈a〉 slip system. The cross girdle in the driest grains suggests activity of prism 〈a〉 and possibly rhomb 〈a〉, whereas the orientation of the wettest grains implies a contribution from prism [c] slip. These slip system interpretations are supported by analyses of intragranular misorientations. These results indicate that water content impacts the relative activity of various slip systems in natural quartz, potentially affecting application of the quartz opening angle thermometer.