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As Huntington’s disease (HD) progresses, there is a significant loss of neurons in the striatum in addition to a distinct thinning of the cerebral cortex. Despite an early presence of sensorimotor deficits in patients with HD, electrophysiological studies designed to assess the integrity of thalamocortical circuits are sparse. Using the R6/2 mouse model of HD, we provide evidence of reduced connectivity between thalamic cells and their targeted cortical regions. Whole-cell patch clamp recordings from ventral anterolateral nucleus (VAL; motor) and ventral posteromedial nucleus (VPM; somatosensory) thalamic neurons inex vivobrain slices of R6/2 and wild-type (WT) mice revealed that cells in both thalamic nuclei of R6/2 mice exhibited significant differences in passive and active cell membrane properties (smaller cell membrane capacitances, faster decay time constants and increased input resistances) compared with WT cells. Although only cells in the VPM of symptomatic R6/2 mice had more depolarized resting membrane potentials compared with WTs, cells in both nuclei displayed increased excitability in symptomatic, but not presymptomatic, R6/2 mice. Optical activation of VAL and VPM terminals elicited smaller magnitude current responses in cortical pyramidal neurons (CPNs) in both motor cortex (M1CTX) and somatosensory barrel cortex (BCTX) of symptomatic R6/2 mice compared with CPNs in WT mice. Furthermore, we observed a decrease in the frequency of thalamocortical excitatory quantal events in R6/2 BCTX CPNs, with no genotype-dependent differences in AMPA:NMDA response amplitude ratios. These data suggest there is a decrease in the transmission of thalamocortical information that is likely because of impaired neurotransmitter release.

Reported here is a coding-complete genome sequence of a SARS CoV-2 variant obtained from raw wastewater samples at the University of Tennessee—Knoxville campus. This sequence provides insight into SARS CoV-2 variants that circulate on large college campuses but remain mostly undetected.

The aim of this study was to investigate how those with pain, and their significant others, perceive the involvement of significant others in a multidisciplinary chronic pain management programme.Semi-structured telephone interviews were conducted with eight people who had attended a Family Day as part of a three-week multidisciplinary chronic pain management programme in Auckland, New Zealand. Four of the participants had pain and four were significant others. Follow-up interviews were conducted with seven of the participants up to one year after their initial interview. Conventional content analysis was used to analyse collected data.Participants viewed the involvement of significant others to be important because managing pain necessitates 'being on the same page' and significant others also needed an opportunity to access support and information.The involvement of significant others in programmes is perceived to be important but must be a balance between what is feasible for significant others and beneficial for all. Further research into when and how significant others are included within programmes is urgently required.

Nonlinear interactions between the two polarizations of the gravitational waves in the Gowdy T3 cosmology cause the generation of small-scale spatial structure from smooth initial data as the singularity is approached. The growth of this structure competes with the freezing of the spatial profile characteristic of the velocity dominated approach to the singularity conjectured for these models. Some properties of this phenomenon will be discussed.

One‐ and two‐dimensional modeling of the Schlumberger soundings at the Roosevelt Hot Springs KGRA have indicated a low‐resistivity zone of approximately 5 Ω-m paralleling the dome fault. The low resistivity of this zone is probably due to intensely fractured and altered water‐saturated rock. A zone of resistivity 12 Ω-m extending to the west of the dome fault is probably due to leakage of brine away from the geothermal system through alluvium or moderately altered rock. A resistive basement underlies the conductive zones and is believed to be essentially nonporous and unaltered rock. A major problem in the application of one‐dimensional (1-D) modeling of Schlumberger data in the Roosevelt Hot Springs KGRA is poor resolution of the 1-D parameters. The joint inversion of Schlumberger and electromagnetic sounding data gives a least‐squares 1-D conductivity model in which parameters are much better resolved than are the model parameters estimated by the inversion of Schlumberger data alone. One‐dimensional modeling of Schlumberger soundings along a traverse does indicate the presence of a 2-D inhomegeneity but it gives no hint of the possible complexity of that inhomogeneity even though the parameters of the models fitting each sounding have acceptable standard deviations when constrained by electromagnetic sounding data. Since the model parameter standard deviations are model dependent, good resolution of 1-D model parameters does not indicate that the assumption of a 1-D model is valid. On the other hand, the possible complexity of structure is brought out by 2-D modeling of the same data, but since the degrees of freedom for complex 2-D models is large, a thorough study of the resolution of such models is prohibited costly at present. In these circumstances, we must constrain the 2-D models with independent geologic or geophysical data and then accept the subsequent best‐fit model as semiquantitative.

Resistivity data on a profile often must be interpreted in terms of a complex two‐dimensional (2-D) model. However, trial‐and‐error modeling for such a case can be very difficult and frustrating. To make interpretation easier and more objective, we have developed a nonlinear inversion technique that estimates the resistivities of cells in a 2-D model of predetermined geometry, based on dipole‐dipole resistivity data. Our numerical solution for the forward problem is based on the transmission‐surface analogy. The partial derivatives of apparent resistivity with respect to model resistivities are equal to a simple function of the currents excited in the transmission surface by transmitters placed at receiver and transmitter sites. Thus, for the dipole‐dipole array the inversion requires only one forward problem per iteration. We use the Box‐Kanemasu method to stabilize the parameter step at each iteration. We have tested our inversion technique on synthetic and field data. In both cases, convergence is rapid and the method is practical if the number of parameters is not too large. The main limitations of the method are that the geometry of the model must be specified in advance, and that it is difficult to determine whether model misfit is due to 3-D effects or to underparameterization in the 2-D model. The technique should be used interactively, with models constrained by geologic information.

Magneto-telluric measurements were carried out at a group of eight sites, from Braunschweig to Lubeck, to determine the resistivity values associated with the North German conductivity anomaly. The data were analyzed for scalar and tensor apparent resistivities over the period range 5–2000 seconds. The results in general indicate very conductive (˜I Ω-m) sediments overlying a resistive basement which is strongly lineated. Interpreted basement depth (˜6 km) is compatible with published seismic refraction data. Principal conductivity axes in the basement appear to be directly related to trends of salt domes and major troughs. A major change in axis direction occurs near the center of the North German anomaly.

The L/M parameter measured in some time‐domain IP systems has been analyzed theoretically by calculating the behavior of this parameter as a funcfion of intrinsic IP response and homogeneous earth EM coupling response. Calculated time‐domain voltage waveforms exhibit graphically the presence of (1) intrinsic IP response, (2) positive EM coupling response, and (3) negative EM coupling response. Quantitatively, L/M remains constant at unity for varying values of intrinsic IP response, and an anomalous L/M value indicates the presence of coupling.

With the use of frequencies in the audio range, the magnetotelluric method can determine subsurface electrical conductivity structure at depths appropriate for mineral exploration. In 1963, Kennecott initiated a program to determine the feasibility of this technique as a geophysical tool. As opposed to the broad‐band recording and subsequent Fourier analysis commonly utilized in low‐frequency magnetotelluric studies, Kennecott’s AMT instrumentation is a multifrequency, narrow‐band, analog system which yields scalar apparent resistivities. Since the natural source fields at frequencies from 10 hz to about 20 khz are due to thunderstorm energy, the AMT technique is most useful in summertime operation, as is Afmag. Considerable experience in the field has led to useful applications in several problems: (a) uniform sedimentary columns, (b) high‐resistivity cover, and (c) massive, layered sulfides. Although of predictably little assistance in problems relating to disseminated mineralization exploration, deep targets, or areas with low‐resistivity cover, the AMT technique can be useful in defining sharp lateral contrasts in resistivity and in “seeing” through high‐resistivity cover.

Resistivity data on a profile often must be interpreted in terms of a complex two-dimensional (2-D) model. However, trial-and-error modeling for such a case can be very difficult and frustrating. To make interpretation easier and more objective, we have developed a nonlinear inversion technique that estimates the resistivities of cells in a 2-D model of predetermined geometry, based on dipole?dipole resistivity data. Our numerical solution for the forward problem is based on the transmission-surface analogy. The partial derivatives of apparent resistivity with respect to model resistivities are equal to a simple function of the currents excited in the transmission surface by transmitters placed at receiver and transmitter sites. Thus, for the dipole?dipole array the inversion requires only one forward problem per iteration. We use the Box?Kanemasu method to stabilize the parameter step at each iteration. We have tested our inversion technique on synthetic and field data. In both cases, convergence is rapid and the method is practical if the number of parameters is not too large. The main limitations of the method are that the geometry of the model must be specified in advance, and that it is difficult to determine whether model misfit is due to 3-D effects or to underparameterization in the 2-D model. The technique should be used interactively, with models constrained by geologic information.