We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
To evaluate the impact of a mobile-app-based central line-associated bloodstream infection (CLABSI) prevention program in nursing home residents with peripherally inserted central catheters (PICCs).
Design:
Pre-post prospective cohort study with baseline (September 2015–December 2016), phase-in (January 2017–April 2017), and intervention (May 2017–December 2018). Generalized linear mixed models compared intervention with baseline frequency of localized inflammation/infection, dressing peeling, and infection-related hospitalizations. Cox proportional hazards models compared days-to-removal of lines with localized inflammation/infection.
Setting:
Six nursing homes in Orange County, California.
Patients:
Adult nursing home residents with PICCs.
Intervention:
CLABSI prevention program consisting of an actionable scoring system for identifying insertion site infection/inflammation coupled with a mobile-app enabling photo-assessments and automated physician alerting for remote response.
Results:
We completed 8,131 assessments of 817 PICCs in 719 residents (baseline: 4,865 assessments, 422 PICCs, 385 residents; intervention: 4,264 assessments, 395 PICCs, 334 residents). The intervention was associated with 57% lower odds of peeling dressings (OR 0.43, 95% CI 0.28–0.64, P < .001), 73% lower local inflammation/infection (OR = 0.27, 95% CI: 0.13–0.56, P < .001), and 41% lower risk of infection-related hospitalizations (OR = 0.59, 95% CI: 0.42–0.83, P = .002). Physician mobile-app alerting and response enabled 62% lower risk of lines remaining in place after inflammation/infection was identified (HR 0.38, CI: 0.24–0.62, P < .001) and 95% faster removal of infected lines from mean (SD) 19 (20) to 1 (2) days.
Conclusions:
A mobile-app-based CLABSI prevention program decreased the frequency of inflamed/infected central line insertion sites, improved dressing integrity, increased speed of removal when inflammation/infection were found, and reduced infection-related hospitalization risk.
Redweed a tropical erect branched herb, is one of the predominant broadleaf weeds affecting upland crops in the Onattukara Sandy Plains, Kerala, India. Experiments were conducted in a screenhouse at the College of Agriculture, Vellayani, Thiruvananthapuram, Kerala, India, to determine the effects of seed burial depth and seed scarification on emergence indices and growth attributes of redweed. Scarification stimulated emergence and resulted in greater values for emergence indices and seedling parameters. The seedling emergence of redweed was influenced by seed burial depth. Shallow seed burial (2 cm) of scarified and non-scarified seeds resulted in greater seedling length (70 cm and 58 cm, respectively), seedling biomass (0.72 g and 0.48 g, respectively), emergence percentage (60% and 32%, respectively), and greater values for other emergence indices. As the depth of seed burial increased from 2 cm, emergence and seedling biomass decreased, exhibiting lower values for the emergence indices. Correlation and regression studies revealed that seed burial depth of scarified and non-scarified seeds greater than 2 cm had a negative effect on seedling emergence and biomass of redweed. Weed biology studies indicated that redweed displayed notable consistency in its phenological traits, regardless of the location where the seeds were collected, as little ecotype variability was observed. Emergence occurred in 6 d, 50% flowering in 44 d, capsule formation in 56 d and maturity in 76 d. On average, a single plant produced 277 seeds and had a 100 seed weight of 0.31 g. A stale seedbed with shallow tillage or deep plowing to a depth of 10 cm before sowing can be adopted to reduce the infestation of redweed.
Direct numerical simulations of the turbulence of a Herschel–Bulkley (HB) fluid in a rough channel are performed at a shear Reynolds number $Re_{\tau } \approx 300$ and a Bingham number ${Bn} \approx 0.9$. For the type of rough surface used in this study, the results indicate that Townsend's wall similarity hypothesis also holds for HB fluids. However, there are notable differences compared with the effect of roughness on Newtonian fluids. More specifically, the effect of roughness appears to be slightly stronger for HB fluids, in the sense that the bulk Reynolds number, based on the viscosity at the wall, is reduced further due to the increase in viscosity in the troughs of the roughness surface induced by the low shear. At the same time, for the simulated rough surface, the contribution of form drag to the total pressure drop is reduced from 1/4 to about 1/5 due to the persistence of viscous shear in the boundary layer, reducing its shielding effect. As for the friction factor, due to the nonlinearity of the HB constitutive relation, its use with the wall shear rate from the mean wall shear stress underpredicts the minimum viscosity at the wall by up to 18 %. This inevitably leads to uncertainties in the prediction of the friction factor. Finally, it is observed that the rough surface is unable to break the peculiar near-wall flow structure of HB fluids, which consists of long persistent low-speed streaks occupying the entire domain. This means that the small-scale energy is significantly reduced for HB fluids, even in rough channels, with the energy more concentrated in the lower wavenumber range, implying an increase in the slope of the power spectrum to $-7/2$ in the inertial range, as shown by Mitishita et al. (J. Non-Newtonian Fluid Mech., vol. 293, 2021, 104570).
In order to recognize the best nutrient supply options for profitable and sustainable production systems, observations were recorded from 2001 to 2020 (20 years) in a long-term fertilizer experiment initiated in 1995–96 with soybean–wheat cropping systems (SWCSs) under irrigated conditions. The experiment comprised of seven treatments including control, organic, inorganic and their combinations. A combined use of 10 Mg farmyard manure (FYM)/ha (M) along with 120 kg N/ha provided statistically (P < 0.05) similar yield and economic benefits to the M + NPK and also provided a positive yield trend (30.0 and 16.2 kg/ha/year) and net return (14.7 and 5.81 US$/ha/year) over the year in both wheat and soybean, respectively. The combined use of organic and chemical fertilizers, provided 32–41% higher production efficiency than their individual use. In contrast, long-term chemical fertilization provided a negative yield trend in both the crops with the highest reduction in sole N-fertilized plots ranged from −39 to −42 kg/ha/year. Water-use efficiency ranged from 3.20 to 12.3 kg/ha/mm in soybean–wheat rotation and increased almost 1.74–3.15 times in wheat and 1.30–1.80 times in soybean due to fertilizer application. A similar trend was observed for water-expense efficiency and remain closely associated with fertilization practice. Long-term chemical fertilizers declined the yield potential of the studied crops while their conjoint application with FYM in the winter season considered as an input efficient approach to sustain the overall productivity and profitability of SWCSs.
In recent times, Health Professionals (HPs) people may feel a sense of discomfort and nervousness when disconnected from their smartphones, causing the emergence of the new phenomenon of “No Mobile Phone Phobia,” or Nomophobia.
Objectives
We aim to study lifestyle-related factors that influence HPs’ Nomophobia.
Methods
From April- June 2023, a global cross-sectional study was conducted using the modified Nomophobia questionnaire (NMP-Q). The original 20 NMP-Q questions (Qs) were reduced to 14 to avoid repetitive Qs with similar meanings. The Qs were categorized into 4 sections, A- Not Being Able to Access Information; B- Losing Connectedness; C- Not Being Able to Communicate; and D- Giving Up Convenience. A new section, “E- Daily Habits”, and “F- Smartphone Type”, and “Hours Spent Daily” were added. Before the launch, it was internally and externally validated by trained psychiatrists as well as experienced researchers. We utilized social media, WhatsApp, text and emails to share it with HPs of different specialties worldwide. The survey was anonymous and IRB-exempt.
Results
Total 105 countries’ HPs participation led to 12,253 responses. Total 47.3% of HPs agreed/strongly agreed (A/SA) that they prefer to use their smartphone before bedtime. Over half (57.8%) of HPs A/SA checked their notifications immediately after waking up in the morning. Only 19.4 % of HPs A/SA that woke up in the middle of the night to check notifications. Total 40.5% of HPs A/SA, 22% were neutral, and 37.3% of HPs disagreed /strongly disagreed (D/SD) with using smartphones while eating their meals. A total of 52.7% of HPs preferred smartphone usage over exercising as a break, while 454.9% of HPs A/SA that they chose smartphones over exploring other hobbies for relaxation. A total of 44.2% of respondents A/SA with smartphone usage in the restroom, 39.8% D/SD. 37.4% of participants D/SD with getting distracted by notifications and resisted the urge to answer any calls or texts while performing a focused task, whereas 39.6% A/SA and 23% were neutral. A total of 80% of respondents met the modified criteria for moderate-severe nomophobia.
Conclusions
In a large-scale survey-based study on Nomophobia, additional Qs in NMP-Q may help recognize that nomophobia can be a result of daily lifestyle decisions rather than an isolated issue.
Hot brewed coffee is the most popular hot beverage in the world, and its health properties have been published in the literature(1). Conversely, over the past decade, cold-brewed coffee has gained popularity, but its eventual nutritional properties are unclear. Both hot and cold brewed coffee produces over 6 million tons of spent coffee grounds (SCG) yearly disposed in landfills(1). Interestingly, studies have shown that SCG can improve several metabolic parameters via changes in the gut microbiome in obese and diabetic rats(2), and reduce energy consumption in overweight humans(3). However, studies investigating the nutritional properties of SCG are lacking in the literature. Hence, in this study, we aimed to identify, quantify and compare two main bioactive compounds in hot- and cold-brewed coffee as a beverage, as well as in the SCG. Samples from hot and cold coffee beverages and SCG were obtained from a local coffee shop (n = 3 per group). The coffee beans were composed of Coffea arabica from Papa New Guinea, Brazil, Ethiopia, and Colombia (in order from highest to lowest proportion). All samples were analysed by high-performance liquid chromatography and mass spectrometry (HPLC-MS). The analyses focused on two main bioactive compounds; trigonelline and chlorogenic acid (CGA). Statistical analyses were performed using an unpaired t-test with Welch’s correction and two-way ANOVA with Tukey’s post-hoc test (p<0.05). When compared to hot-brewed coffee beverages, cold-brewed coffee beverages have shown lower (p<0.05) levels of trigonelline (17.26 mg/g + 1.305 vs. 8.46 mg/g + 0.74, respectively) and CGA (9.82 mg/g + 0.93 vs. 5.31 mg/g + 0.48, respectively). In SCG obtained from hot-brewed coffee, a higher concentration of CGA was found (0.12 mg/g + 0.006), when compared to SCG obtained from cold-brewed coffee (0.10 mg/g + 0.03). However, trigonelline in cold-brewed SCG was found in higher (p<0.05) concentration, when compared to hot-brewed SCG (0.11 mg/g + 0.03 vs. 0.09 mg/g + 0.017, respectively). Moreover, hot-brewed coffee beverages showed higher (p<0.05) concentrations of trigonelline and CGA, when compared to hot-brewed SCG. Similarly, cold-brewed coffee beverages showed higher (p<0.05) concentrations of both bioactive compounds, when compared to cold-brewed SCG. Our results indicated that hot brewed coffee beverage contains high concentrations of bioactive compounds (CGA and trigonelline), which possibly explain its health properties. Although SCG obtained from hot and cold-brewed coffee showed lower concentrations of both bioactive compounds than coffee beverages, our results shed light on the possible health benefits of SCG consumption. In a world seeking more sustainable solutions, further studies investigating the potential use of SCG as a functional food are required.
This contribution focuses on the abatement with hydrogen of CO2 and non-CO2 emissions. It is agenda-setting in two respects. Firstly, it challenges the globally accepted hydrocarbon sustainable aviation fuel (SAF) pathway to sustainability and recommends that our industry accelerates along the hydrogen pathway to ‘green’ aviation. Secondly, it reports a philosophical and analytical investigation of appropriate accuracy on abatement strategies for nitrogen oxides and contrails of large hydrogen airliners. For the second contribution, a comparison is made of nitrogen oxide emissions and contrail avoidance options of two hydrogen airliners and a conventional airliner of similar passenger capacity. The hydrogen aircraft are representative of the first and second innovation waves where the main difference is the weight of the hydrogen tanks. Flights of 1000, 2000, 4000 and 8000 nautical miles are explored. Cranfield’s state of the art simulators for propulsion system integration and gas turbine performance (Orion and Turbomatch) were used for this. There are two primary contributions to knowledge. The first is a new set of questions to be asked of SAF and hydrogen decarbonising features. The second is the quantification of the benefits from hydrogen on non-CO2 emissions. For the second generation of long-range hydrogen-fuelled aircraft having gas turbine propulsion, lighter tanks (needing less thrust and lower gas temperatures) are anticipated to reduce NOx emissions by over 20%; in the case of contrails, the preliminary findings indicate that regardless of the fuel, contrails could largely be avoided with fuel-burn penalties of a few per cent. Mitigating action is only needed for a small fraction of flights. For conventional aircraft this penalty results in more CO2, while for hydrogen aircraft the additional emission is water vapour. The conclusion is that our research community should continue to consider hydrogen as the key ‘greening’ option for aviation, notwithstanding the very significant costs of transition.
A survey for slug- and snail-associated nematodes was conducted in forests, parks, botanical gardens, and nature reserves at 13 localities in Belgium to uncover more diversity of gastropod mollusc-associated nematodes and to characterise Pellioditis populations found in the country. A total of 319 slugs and snails belonging to nine species were examined. Arion vulgaris was the most commonly found mollusc species in this study (eight locations), and 19.4% of the examined mollusc specimens were found infected by nematodes. The highest prevalence of nematodes was observed in Cornu aspersum (60%) followed by A. vulgaris (34.8%), Limax maximus (28.6%), and Cepaea sp. (20%). Eleven nematode species belonging to eight families were isolated and identified from the mollusc hosts including Alloionema appendiculatum, Angiostoma dentiferum, A. gandavense, Angiostrongylus vasorum, Cosmocerca longicauda, Panagrolaimus cf. subelongatus, Pellioditis californica, P. hermaphrodita, Rhabditis sp., Tetrameres cf. fissispina, and Troglostrongylus cf. brevior.Pellioditis was the most commonly found nematode genus (at nine localities) and C. longicauda and P. californica were reported in Belgium for the first time. Co-infections of more than one nematode species were observed in eight (2.5%) molluscs specimens. Most co-infections consisted of two nematode species. In one A. vulgaris specimen, a co-infection of three nematode species (A. vasorum, P. hermaphrodita, and Tetrameres cf. fissispina) was observed. Four ex vivo cultures of P. californica and six ex vivo cultures of P. hermaphrodita were established from single hermaphrodites, and both species were described based on light microscopy, scanning electron microscopy, and morphometric, morphological, and molecular data.
We evaluated whether universal chlorhexidine bathing (decolonization) with or without COVID-19 intensive training impacted COVID-19 rates in 63 nursing homes (NHs) during the 2020–2021 Fall/Winter surge. Decolonization was associated with a 43% lesser rise in staff case-rates (P < .001) and a 52% lesser rise in resident case-rates (P < .001) versus control.
Tight focusing with very small f-numbers is necessary to achieve the highest at-focus irradiances. However, tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance. We describe several near-infrared, visible, ultraviolet and soft and hard X-ray diagnostics employed in a ∼1022 W/cm2 laser–plasma experiment. We used nearly 10 J total energy femtosecond laser pulses focused into an approximately 1.3-μm focal spot on 5–20 μm thick stainless-steel targets. We discuss the applicability of these diagnostics to determine the best in-focus target position with approximately 5 μm accuracy (i.e., around half of the short Rayleigh length) and show that several diagnostics (in particular, 3$\omega$ reflection and on-axis hard X-rays) can ensure this accuracy. We demonstrated target positioning within several micrometers from the focus, ensuring over 80% of the ideal peak laser intensity on-target. Our approach is relatively fast (it requires 10–20 laser shots) and does not rely on the coincidence of low-power and high-power focal planes.
The incorporation of transition metals into hematite may limit the aqueous concentration and bioavailabity of several important nutrients and toxic heavy metals. Before predicting how hematite controls metal-cation solubility, we must understand the mechanisms by which metal cations are incorporated into hematite. Thus, we have studied the mechanism for Ni2+ and Mn3+ uptake into hematite using extended X-ray absorption fine structures (EXAFS) spectroscopy. EXAFS measurements show that the coordination environment of Ni2+ in hematite corresponds to that resulting from Ni2+ replacing Fe3+. No evidence for NiO or Ni(OH)2 was found. The infrared spectrum of Ni-substituted hematite shows an OH-stretch band at 3168 cm−1 and Fe-OH bending modes at 892 and 796 cm−1. These vibrational bands are similar to those found in goethite. The results suggest that the substitution of Ni2+ for Fe3+ is coupled with the protonation of one of the hematite oxygen atoms to maintain charge balance.
The solubility of Mn3+ in hematite is much less extensive than that of Ni2+ because of the strong Jahn-Teller distortion of Mn3+ in six-fold coordination. Structural evidence of Mn3+ substituting for Fe3+ in hematite was found for a composition of 3.3 mole % Mn2O3. However a sample with nominally 6.6 mole % Mn2O3 was found to consist of two phases: hematite and ramsdellite (MnO2). The results indicate that for cations, such as Mn3+ showing a strong Jahn-Teller effect, there is limited substitution in hematite.
A well-characterized kaolinite has been hydrated in order to test the hypothesis that platey kaolinite will roll upon hydration. Kaolinite hydrates are prepared by repeated intercalation of kaolinite with potassium acetate and subsequent washing with water. On hydration, kaolinite plates roll along the major crystallographic directions to form tubes identical to proper tubular halloysite. Most tubes are elongated along the b crystallographic axis, while some are elongated along the a axis. Overall, the tubes exhibit a range of crystallinity. Well-ordered examples show a 2-layer structure, while poorly ordered tubes show little or no 3-dimensional order. Cross-sectional views of the formed tubes show both smoothly curved layers and planar faces. These characteristics of the experimentally formed tubes are shared by natural halloysites. Therefore, it is proposed that planar kaolinite can transform to tubular halloysite.
In recent years, some scientists have called for research into and potential development of ‘solar geoengineering’ technologies as an option to counter global warming. Solar geoengineering refers to a set of speculative techniques to reflect some incoming sunlight back into space, for example, by continuously spraying reflective sulphur aerosols into the stratosphere over several generations. Because of the significant ecological, social, and political risks posed by such technologies, many scholars and civil society organizations have urged governments to take action to prohibit the development and deployment of solar geoengineering techniques. In this article we take such calls for a prohibitory or a non-use regime on solar geoengineering as a starting point to examine existing international law and governance precedents that could guide the development of such a regime. The precedents we examine include international prohibitory and restrictive regimes that impose bans or restrictions on chemical weapons, biological weapons, weather modification technologies, anti-personnel landmines, substances that deplete the ozone layer, trade in hazardous wastes, deep seabed mining, and mining in Antarctica. We also assess emerging norms and soft law in anticipatory governance of novel technologies, such as human cloning and gene editing. While there is no blueprint for a solar geoengineering non-use regime in international law, our analysis points to numerous specific elements on which governments could draw to constrain or impose an outright prohibition on the development of technologies for solar geoengineering, should they opt to do so.
Nursing home residents may be particularly vulnerable to coronavirus disease 2019 (COVID-19). Therefore, a question is when and how often nursing homes should test staff for COVID-19 and how this may change as severe acute respiratory coronavirus virus 2 (SARS-CoV-2) evolves.
Design:
We developed an agent-based model representing a typical nursing home, COVID-19 spread, and its health and economic outcomes to determine the clinical and economic value of various screening and isolation strategies and how it may change under various circumstances.
Results:
Under winter 2023–2024 SARS-CoV-2 omicron variant conditions, symptom-based antigen testing averted 4.5 COVID-19 cases compared to no testing, saving $191 in direct medical costs. Testing implementation costs far outweighed these savings, resulting in net costs of $990 from the Centers for Medicare & Medicaid Services perspective, $1,545 from the third-party payer perspective, and $57,155 from the societal perspective. Testing did not return sufficient positive health effects to make it cost-effective [$50,000 per quality-adjusted life-year (QALY) threshold], but it exceeded this threshold in ≥59% of simulation trials. Testing remained cost-ineffective when routinely testing staff and varying face mask compliance, vaccine efficacy, and booster coverage. However, all antigen testing strategies became cost-effective (≤$31,906 per QALY) or cost saving (saving ≤$18,372) when the severe outcome risk was ≥3 times higher than that of current omicron variants.
Conclusions:
SARS-CoV-2 testing costs outweighed benefits under winter 2023–2024 conditions; however, testing became cost-effective with increasingly severe clinical outcomes. Cost-effectiveness can change as the epidemic evolves because it depends on clinical severity and other intervention use. Thus, nursing home administrators and policy makers should monitor and evaluate viral virulence and other interventions over time.
Quinclorac controls crabgrass (Digitaria spp.) in cool- and warm-season turfgrass species. Herbicide-resistant smooth crabgrass [Digitaria ischaemum (Schreb.) Schreb. ex Muhl.] biotypes have evolved due to recurrent usage of quinclorac. Two Mississippi populations (MSU1 and MSU2) of D. ischaemum were characterized using standard greenhouse dose–response screens to assess their resistance relative to known susceptible populations. Subsequent investigations explored mechanisms of resistance, including examining cyanide accumulation, glutathione S-transferase (GST) activity, and the potential involvement of cytochrome P450s in MSU1, MSU2, and a susceptible (SMT2). Resistant populations MSU1 and MSU2 required 80 and 5 times more quinclorac, respectively, to reach 50% biomass reduction than susceptible populations. The SMT2 biotype accumulated three times more cyanide than the resistant MSU1 and MSU2 populations. GST activity was elevated in resistant MSU1 and MSU2 populations. Furthermore, quinclorac concentrations in treated resistant populations were elevated when plants were pretreated with the P450 inhibitor malathion. These findings suggest a non–target site based mechanism of resistance involving the accumulation of cyanide. This may provide a scientific basis for understanding the occurrence of quinclorac-resistant D. ischaemum, although further research is needed to investigate potential target-site mechanisms of resistance.
This paper proposes a lightweight frequency selective surface polarization-insensitive wideband metamaterial absorber in C band and X band that employs only a few resistive elements. The proposed absorber is embodied with four quadrature slotted inner circular patch, which is horizontally and vertically bisected, and outer concentric copper rings of 0.035 mm thickness are attached with four lumped resistors placed at 90° apart. A slotted inner circular patch provides significant inductive and capacitive loading. The absorption bandwidth of 8.02 GHz with more than 90% absorption is observed from 5.69 to 13.71 GHz under normal incidence and maintains almost same absorptivity range under oblique incidence up to 45° in both transverse electric mode and transverse magnetic mode. The designed metamaterial absorber is fabricated and measured using free space measurement technique. The actual experiments and the simulated ones are in good agreement.
Diagnostic stewardship seeks to improve ordering, collection, performance, and reporting of tests. Test results play an important role in reportable HAIs. The inclusion of HAIs in public reporting and pay for performance programs has highlighted the value of diagnostic stewardship as part of infection prevention initiatives. Inappropriate testing should be discouraged, and approaches that seek to alter testing solely to impact a reportable metric should be avoided. HAI definitions should be further adapted to new testing technologies, with focus on actionable and clinically relevant test results that will improve patient care.
We have employed the VULCAN laser facility to generate a laser plasma X-ray source for use in photoionization experiments. A nanosecond laser pulse with an intensity of order 1015 Wcm−2 was used to irradiate thin Ag or Sn foil targets coated onto a parylene substrate, and the L-shell emission in the 3.3–4.4 keV range was recorded for both the laser-irradiated and nonirradiated sides. Both the experimental and simulation results show higher laser to X-ray conversion yields for Ag compared with Sn, with our simulations indicating yields approximately a factor of two higher than those found in the experiments. Although detailed angular data were not available experimentally, the simulations indicate that the emission is quite isotropic on the laser-irradiated side but shows close to a cosine variation on the nonirradiated side of the target as seen experimentally in the previous work.
Purified soil kaolins from Indonesia and Western Australia were characterized using analytical TEM, XRD, TGA and chemical analysis. The Indonesian kaolins, formed from tuff, consist of a mixture of tubular kaolin crystals with relatively low Fe concentrations and platy kaolin crystals with higher Fe concentrations. Western Australian kaolins also contained tubular and platy crystals but showed no systematic relationship of crystal morphology with Fe content. The coherently scattering domain (CSD) size of the Indonesian samples (5–6 nm for 001, i.e. c axis dimension) is remarkably consistent and is approximately half of the value for the Western Australian kaolins (9.7–13.4 nm), and both are much smaller sizes than values for the reference kaolins (15.6–27.8 nm). Coherently scattering domain sizes derived from the Scherrer equation are approximately twice the values obtained from the Bertaut-Warren-Averbach Fourier method but the results show the same pattern of variation. For the Indonesian, Western Australian and reference kaolins, the N2-BET surface area ranges 59–88, 44–56 and 5–28 m2/g; the dehydroxylation temperatures range 486–499, 484–496 and 520–544°C, the mean cation exchange capacities (CEC) are 9.4, 5.0 and 3.5 meq 100 g−1 and the surface densities of charge range 0.10–0.14, 0.08–0.10 and 0.04–0.12 C/m2. The properties of the Western Australian kaolins and Indonesian kaolins differ substantially, but kaolins within each group have similar properties. These results suggest that soil kaolin properties may be characteristic of a particular pedoenvironment and that a systematic study of kaolins in different pedoenvironments is required.