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The Dixie Valley fault bounds the east side of the Stillwater Range in west‐central Nevada and last ruptured in 1954. Offset basalts indicate that slip began more recently than ~14 Ma, and prior work has interpreted the southern segment as an active low‐angle normal fault. Oligocene igneous rocks in the southern Stillwater Range were steeply tilted during large‐magnitude extension prior to ~14 Ma. To refine the timing of early extension and the onset of slip on the Dixie Valley fault, we collected two transects of samples for apatite fission track, apatite and zircon (U‐Th)/He (AHe and ZHe), and apatite 4He/3He thermochronometry. Apatite fission track ages from the Oligocene IXL pluton indicate rapid cooling ~18–14 Ma, and AHe and ZHe ages from the Cretaceous La Plata Canyon pluton indicate rapid cooling ~16–19 Ma. We interpret these data to record cooling during rapid extension. AHe ages from the IXL pluton are ~6–8 Ma and record cooling during slip on the Dixie Valley fault. We modeled these ages and 4He/3He spectra from one sample as the result of cooling during exhumation of a tilted fault block at a constant extension rate. The model predicts slip on the Dixie Valley fault beginning ~8 Ma. Although it does not constrain the initial fault dip, the model illustrates how a low‐angle fault requires a higher extension rate to reproduce cooling ages. Consequently, we prefer a high‐angle southern Dixie Valley fault for strain compatibility with the high‐angle northern segment. Key Points: Oligocene volcanic rocks in the southern Stillwater Range were tilted during Miocene (18–14 Ma) extensionSlip on the Dixie Valley fault began ~8 Ma [ABSTRACT FROM AUTHOR]

Low‐temperature thermochronometry is widely used to measure the timing and rate of slip on normal faults. Rates are often derived from suites of footwall thermochronometer samples, but regression of age versus structural depth fails to account for the trajectories of samples during fault slip. We demonstrate that in rotating fault blocks, regression of age‐depth data is susceptible to significant errors (>10%) in the identification of the initiation and rate of faulting. Advection of heat and topographic growth influence the thermal histories of exhumed particles, but for a range of geologically reasonable fault geometries and rates these effects produce Apatite (U‐Th)/He ages comparable to those derived from rotation through fixed isotherms. We apply the fixed‐isotherm model to published data from the Pine Forest Range and the East Range, Nevada, by incorporating field and thermochronologic constraints into a Markov chain Monte Carlo model. Modeled parameters for the Pine Forest Range are described by narrow ranges of geologically reasonable values. Compared to slip rates of 0.3–0.8 km/Myr and an initiation of faulting ca. 11–12 Ma derived from visual inspection, the model predicts an average slip rate of ~1.1 km/Myr and an onset of faulting ca. 9–10 Ma. For the East Range fault block the model suggests that faulting began ~17 Ma with an extension rate of ~3 km/Myr and slowed to an extension rate of ~0.5 km/Myr at ~14 Ma. The absence of a preserved partial retention zone in the East Range sample set limits how well the model can predict fault block geometry. Plain Language Summary: Normal faults form in settings where the crust is extending and can be associated with both seismic hazards and natural resource emplacement. To learn about the history of normal faults we often turn to minerals that record the history of cooling that occurs as fault slip carries rocks from depth to the relatively cool surface of the Earth. To interpret these cooling histories, it is common practice to treat the cooling of these minerals as resulting from the vertical translation of a series of samples through the crust. However, this ignores the basic geologic observation that sets of samples are often collected from areas that have undergone rotation as well as vertical translation. Here we investigate how this rotation may complicate the interpretations we make about fault histories by simulating the cooling histories of minerals that undergo faulting and associated rotation. We find that traditional methods for inferring slip histories on faults may be significantly biased and propose a relatively simple alternative for investigating these systems that is consistent with our geologic observations. Key Points: Curved particle trajectories in tilted normal fault blocks complicate the interpretation of thermochronometer agesSimple interpretation of age‐versus‐structural depth plots can significantly mispredict the onset and rate of faultingTwo examples from the Basin and Range Province of Nevada reveal promise for quantitative inference of slip history from kinematic descriptions of sample paths [ABSTRACT FROM AUTHOR]

This article describes the technique of saphenous vein peripherally inserted central catheter placement, which is used as an alternative site for venous access in our institution, and examines saphenous vein peripherally inserted central catheter safety issues and indications. Three end-stage renal failure patients, two patients diagnosed with malignancy and one renal transplant patient had a saphenous peripherally inserted central catheter (inserted between March 2004 and March 2006 for antibiotics or chemotherapy. The average duration of placement was 16.2 days (range 3–42 days). All insertions were carried out successfully, with an average screening time of 81.2 s. None of the patients experienced any major complications. Two patients developed localized cellulitis at the insertion site. [ABSTRACT FROM AUTHOR]

Peripheral nerve disorders may be classified into compressive or entrapment neuropathies and non-compressive neuropathies. Muscle denervation recognized on MRI may be a useful sign in the diagnosis of peripheral nerve disorders. Acute or subacute denervation results in prolonged T2 relaxation time, producing increased signal in skeletal muscle on short tau inversion-recovery and fat-suppressed T2-weighted images. Chronic denervation produces fatty atrophy of skeletal muscles, resulting in increased muscle signal on T1-weighted images. This review will outline and illustrate the various ways that muscle denervation as seen on MRI may assist in the diagnosis and localization of peripheral nerve disorders. [ABSTRACT FROM AUTHOR]

Cannabis, commonly known as marijuana, is the most frequently used illicit drug in Australia. Therefore, oral health care providers are likely to encounter patients who are regular users. An upward trend in cannabis use is occurring in Australia, with 40 per cent of the population aged 14 and above having used the drug. There are three main forms of cannabis: marijuana, hash and hash oil, all of which contain the main psychoactive constituent delta-9-tetrahydrocannabinol (THC). Cannabis is most commonly smoked, however it can be added to foods. THC from cannabis enters the bloodstream and exerts its effects on the body via interaction with endogenous receptors. Cannabis affects almost every system of the body, particularly the cardiovascular, respiratory and immune systems. It also has acute and chronic effects on the mental health of some users. Therefore, chronic abuse is a concern because of its negative effects on general physical and mental health. Cannabis abusers generally have poorer oral health than non-users, with an increased risk of dental caries and periodontal diseases. Cannabis smoke acts as a carcinogen and is associated with dysplastic changes and pre-malignant lesions within the oral mucosa. Users are also prone to oral infections, possibly due to the immunosuppressive effects. Dental treatment on patients intoxicated on cannabis can result in the patient experiencing acute anxiety, dysphoria and psychotic-like paranoiac thoughts. The use of local anaesthetic containing epinephrine may seriously prolong tachycardia already induced by an acute dose of cannabis. Oral health care providers should be aware of the diverse adverse effects of cannabis on general and oral health and incorporate questions about patients' patterns of use in the medical history. [ABSTRACT FROM AUTHOR]

Aim. Studies of the descriptions of pain by children have neglected their linguistic development, therefore estimates of dental pain in children may not be accurate. This study sought (1) to identify words chosen by children to describe dental pain and (2) to establish the effect of linguistic development on that description. Sample. Seventy-eight consecutive children between the ages of 5 and 13 years attending a paediatric dental clinic. Method. Each child completed the WORD reading comprehension test. They then underwent a pulp test and a simulated pulp test, administered by a dentist in a counterbalanced order, of a healthy primary canine or permanent incisor, according to the child’s age. To describe each test, the children had to (1) select words from a list of 58 read by the experimenter and (2) give ratings on scales representing ‘sore’ and ‘tingly’. Results. Analysis of variance confirmed that the children chose more words for the pulp test than for the simulated test (P < 0·001); the former also elicited higher ratings for ‘sore’ and ‘tingly’. The numbers of words chosen were transformed by a square root constant to ensure a normal distribution. Multiple regression analysis then showed that (1) the better the children’s reading comprehension, the fewer words they chose, possibly because they were less inclined to choose unfamiliar words, and (2) the older they were, the more words they chose, possibly because of having more experience of pain. There were similar findings for ratings of ‘sore’ and ‘tingly’. Conclusions. To assess children’s experience of pain (1) they need to be presented with a list of words like the ones in this study, (2) the numbers of words chosen by them would represent the severity of pain, and (3) those numbers need to be adjusted for the children’s reading comprehension and age. [ABSTRACT FROM AUTHOR]

This report describes 7-year-old Afro-Caribbean monozygotic twin boys who both presented with bilateral unerupted mesiodentes palatal to the central incisors. There have been two previous similar reports. From this case and previous reports it was concluded that mesiodentes in monozygotic twins are likely to be concordant with respect to the number of supernumerary teeth. Unilateral mesiodens usually have been mirror imaged in each twin. Minor discordance between monozygotic twins is common with respect to the shape (conical, incisiform or tuberculate) and orientation (inverted or normal) of individual mesiodens within and between each twin. [ABSTRACT FROM AUTHOR]