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The aim of this study was to examine the cognitive function in chronic ketamine users. Factors correlated to cognition impairments were analyzed. Sixty-three chronic ketamine users and 65 healthy subjects were recruited. Cognitive function was assessed by using immediate/delayed visual reproduction (IVR/DVR) tasks, immediate/delayed logical memory (ILM/DLM) tasks, Stroop test, Wisconsin card sorting test (WCST), and continuous performance test (CPT). Psychopathological symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS), Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). Ketamine users performed worse than controls on the IVR, ILM, DLM, Stroop and auditory CPT tests. IVR and DVR, color-naming and color-interference-reading scores were positively correlated with education level. In ketamine users ILM scores were negatively correlated with the negative subscale of PANSS. DLM score was positively correlated with average dose of ketamine use. Word-reading score was positively correlated with education level, and negatively correlated with duration of ketamine use. False hits in auditory CPT was positively correlated with duration of ketamine use. Number of trials to complete the first category and perseverative errors on WCST were positively correlated with the duration between the test and last ketamine use. Chronic ketamine users had cognitive impairments across multiple domains.

International audience; The deepest valleys of the Andes have been cut in southern Peru by the Ríos Cotahuasi Ocoña and Colca–Majes. These canyons are Late Miocene landforms based on a new ignimbrite stratigraphy supported by 42 new 40Ar/39Ar age determinations obtained on plateau-forming and valley-filling ignimbrites. Between 19 and 13 Ma, a gently sloping surface bevelling the clastic wedge southeast of the developing mountain front was mantled by widespread ignimbrites. After 13 Ma, this paleosurface was tilted up from 2.2 km a.s.l. at the mountain front to 4.3 km a.s.l. at the base of the Pliocene and Pleistocene volcanoes that crown the southwestern edge of the Altiplano. The canyons incised this topography after 9 Ma, while the dated base of younger ignimbrite valley fills suggests that these canyons had been cut down to near their present depths as early as 3.8 Ma. By 1.4 Ma, however, the canyons had been almost completely refilled by 1.3 km-thick unwelded pyroclastic deposits, which were subsequently eroded. Valley incision since 9 Ma at an average rate of 0.2 mm yr−1 is the response to topographic uplift after 13 Ma combined with increasing runoff due to a wetter climate recorded after 7 Ma. Although long-term aridity generated an imbalance between high long-term uplift rates and low plateau denudation rates, the combination of aridity and volcanism still promoted canyon incision because episodic volcanic fills maintained a cycle of catastrophic debris avalanches and subsequent dam breakouts.

Statherian siliciclastic sedimentary rocks in the southern Lake Superior region are key to understanding the evolution and stabilization of Paleoproterozoic crust in the midcontinent. Deposited during an important period of significant crustal growth, controversy exists regarding the conditions of sandstone deposition and the relations between magmatism and sedimentation. In central Wisconsin, the Hamilton Mounds inlier, although restricted in areal extent, is significant in that it reveals the existence of two separate Statherian units: an 1800–1760 Ma immature meta-arkose and a post-1760 Ma Baraboo Interval supermature quartzite. The meta-arkose is crosscut by 1762 Ma granite and contains abundant Penokean age detrital monazite grains. The younger quartzite contains detrital monazite as young as 1750 Ma and was deposited unconformably upon these older units. All units experienced 1630 Ma low-grade recrystallization and isotopic disturbance associated with the Mazatzal Orogeny. In addition, the supermature quartzite experienced K-metasomatism and brecciation at 1470 Ma, ascribed to regional-scale hydrothermal alteration related to the influence of the nearby 1470 Ma Wolf River batholith. Collectively, these data suggest an early Statherian episode of arkosic deposition and magmatism during Yavapai orogenesis, followed by a longer interval of deposition of supermature quartz arenite associated with crustal stabilization. The existence of two separate Statherian units reconciles apparent conflicts in depositional models and provides a greater understanding of the Paleoproterozoic evolution of the midcontinent.

Two perpendicular ultramafic lamprophyre dikes on Little Presque Isle near Marquette, Michigan were studied to compare their intrusive magmatic fabric using anisotropy of magnetic susceptibility (AMS) with the strains preserved by mechanical twins in dike magmatic calcite (δ18O = −21.93, δ13C = −4.53) and dike-margin hydrothermal calcite (δ18O = −9.72, δ13C = −3.76) veins. Phlogopite from the lamprophyres yield an 40Ar–39Ar plateau age of 1877 Ma, and the lamprophyres intrude metadiabase dikes and the Compeau Creek gneiss (2691 ± 25 Ma; LA-ICPMS U–Pb on zircon), all of which is cross-cut by Keweenaw basaltic dikes and unconformably overlain by the undeformed Jacobsville Sandstone (Meso- to Neoproterozoic). The lamprophyre dikes strike east–west and north–south in this small (3 km2), complex outcrop. Analysis of mechanically twinned calcite in the E–W dike (n = 89 grains, 26.97% NEVs) reveals a sub-horizontal dike-acute shortening strain axis (N38°E, 15°). Strain analysis of the N–S dike (n = 107 grains, 22.43% NEVs) reveals a sub-horizontal and dike-parallel shortening strain axis (N17°E, 14°). Calcite veins from the margins of both lamprophyre dikes reveal a NE–SW sub-horizontal shortening, and both the lamprophyres and vein calcite preserve a vertical shortening strain overprint. Differential stress magnitudes for twinning the lamprophyre calcite and adjacent veins was −35 MPa. AMS analyses, used as a proxy for the primary magmatic flow direction, reveal a sub-horizontal and dike-parallel Kmax, with a dike-normal Kmin for the E–W dike. The N–S dike preserves a vertical Kmax and a dike-normal Kmin. Hysteresis studies on both dikes show that this anisotropy is carried by multi-domain ferromagnetic minerals. These lamprophyres preserve a complex, local intrusive fabric (AMS) that was unaltered by Penokean sub-horizontal shortening (∼SW–NE), or the younger, sub-vertical shortening strain overprint ∼200 km inboard of the unrestored Penokean margin. The twinning strain results are consistent with other Penokean finite strains but not with the strain fabrics of younger orogens (e.g., Yavapai, Mazatzal, Keweenaw-Grenville).

Objective Studies of the effects of the N-methyl-d-aspartate (NMDA) glutamate receptor antagonist, ketamine, have suggested similarities to the symptoms of schizophrenia. Our primary goal was to evaluate the dimensions of the Positive and Negative Syndrome Scale (PANSS) in ketamine users (acute and chronic) compared to schizophrenia patients (early and chronic stages). Method We conducted exploratory factor analysis for the PANSS from four groups: 135 healthy subject administrated ketamine or saline, 187 inpatients of ketamine abuse; 154 inpatients of early course schizophrenia and 522 inpatients of chronic schizophrenia. Principal component factor analyses were conducted to identify the factor structure of the PANSS. Results Factor analysis yielded five factors for each group: positive, negative, cognitive, depressed, excitement or dissociation symptoms. The symptom dimensions in two schizophrenia groups were consistent with the established five-factor model (Wallwork et al., 2012). The factor structures across four groups were similar, with 19 of 30 symptoms loading on the same factor in at least 3 of 4 groups. The factors in the chronic ketamine group were more similar to the factors in the two schizophrenia groups rather than to the factors in the acute ketamine group. Symptom severities were significantly different across the groups (Kruskal–Wallis χ2(4) = 540.6, p

BACKGROUND & OBJECTIVE: In recent years there have been many cases of violence against healthcare professionals (HCPs) in China leading to the death of some doctors as well as nurses by patient's relatives. Our objective was to identify the causative factors for these violent acts and address these isssues which is vital to ensure patient safety. METHODS: A multidisciplinary research task force was formed to do a root cause analysis of the violent acts against the healthcare professionals. A flowchart was developed to identify the steps in the process and discover the potential links. RESULTS: There are complex reasons behind the violence against HCPs. However, the main reasons were found to be poor quality of medical services and increased awareness of patients' rights and their willingness to knock at the doors of courts to seek justice. The feasible counter measures includes stimulating hospital directors to improve patient safety, aligning incentives with quality of service provided in healthcare facilities, monitoring educational quality of HCPs, making necessary changes in medical education programmes besides setting up a reasonable academic promotion mechanism for health professionals based on merit and competence. CONCLUSION: Poor quality of medical services, increased awareness among patients about their rights has resulted in increase in medical disputes and at times violence against healthcare professionals. A number of effective measures can be undertaken by the government, hospitals, and medical schools ensuring patient safety. However, it is essential to sensitize the hospital directors to elevate their quality of medical services. Language: en

This study investigated the serum levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in a group of chronic ketamine abusers in comparison to healthy controls. The correlations between the serum BDNF, NGF level with the subjects' demographic, pattern of ketamine use were also examined.93 subjects who met the criteria of ketamine dependence and 39 healthy subjects were recruited. Serum BDNF and NGF levels were assayed by enzyme-linked immunosorbent assay (ELISA). Psychopathological symptoms were assessed using Positive and Negative Syndrome Scale (PANSS), Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI).Both serum levels of BDNF and NGF were significant lower in the ketamine users compared to the healthy control subjects (9.50±6.68 versus 14.37±6.07 ng/ml, p=0.019 for BDNF; 1.93±0.80 versus 2.60±1.07 ng/ml, p=0.011 for NGF). BDNF level was negatively associated with current frequency of ketamine use (r=-0.209, p=0.045).Both BDNF and NGF serum concentrations were significantly lower among chronic ketamine users than among health controls.

[1] The Indus River is the only major drainage in the western Himalaya and delivers a long geological record of continental erosion to the Arabian Sea, which may be deciphered and used to reconstruct orogenic growth if the modern bedload can be related to the mountains. In this study we collected thermochronologic data from river sediment collected near the modern delta. U-Pb ages of zircons spanning 3 Gyr show that only ∼5% of the eroding crust has been generated since India-Asia collision. The Greater Himalaya are the major source of zircons, with additional contributions from the Karakoram and Lesser Himalaya. The 39Ar/40Ar dating of muscovites gives ages that cluster between 10 and 25 Ma, differing from those recorded in the Bengal Fan. Biotite ages are generally younger, ranging 0–15 Ma. Modern average exhumation rates are estimated at ∼0.6 km/m.y. or less, and have slowed progressively since the early Miocene (∼20 Ma), although fission track (FT) dating of apatites may indicate a recent moderate acceleration in rates since the Pliocene (∼1.0 km/m.y.) driven by climate change. The 39Ar/40Ar and FT techniques emphasize the dominance of high topography in controlling the erosional flux to the ocean. Localized regions of tectonically driven, very rapid exhumation (e.g., Nanga Parbat, S. Karakoram metamorphic domes) do not dominate the erosional record.

We compare geodetic velocity to geologic fault slip rates to show that tectonic loading was doubled across the eastern California shear zone (ECSZ) during a cluster of major earthquake activity. New slip rates are presented for six dextral faults that compose the ECSZ in the central Mojave Desert. These rates were determined from displaced alluvial fans dated with cosmogenic 10 Be and from a displaced lava flow dated with 40 Ar/ 39 Ar. We find that the sum geologic Mojave ECSZ slip rate, ≤6.2 ± 1.9 mm/yr, is only half the present-day geodetically measured velocity of 12 ± 2 mm/yr. These rates account for cumulative fault slip and geodetic observations that span the 60-km-wide shear zone; therefore this difference cannot be attributed to postseismic relaxation. Redistribution of tectonic loading over the earthquake cycle at a regional scale suggests that earthquake clustering may be enhanced via feedback with weakening of ductile shear zones.