Background and purpose
The present study aimed to examine how long‐term migration to high‐altitude regions affects mentality and cognition, and the correlation with various physiological and ...biochemical changes.
Methods
The WHO Neurobehavioral Core Test Battery, Raven's Standard Progressive Matrices (RSPM) and Pittsburgh Sleep Quality Index questionnaire were used to assess 141 young male subjects who lived in plain regions and 217 young male subjects who had migrated to a 4500 m high‐altitude region and lived there for 1–5 years. Arterial oxyhemoglobin saturation, cerebral tissue oxygenation indices (TOIs), serum S100B and brain‐derived neurotrophic factor (BDNF) were also measured.
Results
Long‐term migrators to a high‐altitude region exhibited exacerbated mood disorders, retarded color discrimination ability, decreased visual memory capacity, and impaired perceptual motor skill and motion stability. In addition, the migrators exhibited lower RSPM scores and lower sleep quality. Further analyses revealed significant correlations between sleep quality and cerebral TOIs, mood and sleep quality, mood and certain cognitive functions, mood and serum BDNF levels, and RSPM scores and serum S100B levels.
Conclusions
Long‐term living at high altitudes causes significant impairment of psychological and cognitive function. Cerebral hypoxic extent, sleep quality and biochemical dysfunction are major influencing factors.
•Full-field strain and strain-rate fields of rock was obtained by high-speed 3D-DIC.•The 256 × 256 pixels and 200,000 fps are suggested in dynamic measurement of rock.•Wave propagation, dispersion ...and radial inertial effect on the specimen were found.•The comparison was conducted between 2D- and 3D-DIC in strain measurement.•The failure of sandstone is a shear mode in the test of split Hopkinson pressure bar.
Full-field strain and strain-rate fields of rock materials under dynamic compression were studied by the high-speed three-dimensional digital image correlation (3D-DIC) method. A series of dynamic tests was conducted on Hawkesbury sandstones using a split Hopkinson pressure bar (SHPB) at three different strain rates. The real-time images of the loaded specimen were captured by two high-speed cameras at a frame rate of 200,000 frames per second (fps) with a resolution of 256 × 256 pixels. Wave propagation, dispersion and radial inertial effect on the specimen were found by DIC results. The strain rate vibration pattern on the specimen, which was visualised by DIC, found to be dependent on the input waveform. A recovery of strain in the post-peak stage was detected on the specimen by DIC, which is unrevealed in the traditional one-dimensional theory method (i.e., strain gauge signals). The results showed that strain localisation initiated from the interface of the bar and specimen with the order of tensile, shear and vertical. The initiation of crack from strain localisation is found rate-independent. Comparison between 2D- and 3D-DIC in strain measurement of the same experiment showed that the error in the strain obtained by 2D-DIC could be up to 32%.
This study aimed to assess the prognostic value of the serum albumin to globulin ratio (AGR) in cholangiocarcinoma patients after surgery.
We retrospectively enrolled 123 cholangiocarcinoma patients ...who underwent surgical treatment between June 2003 and September2014 at the Third Affiliated Hospital of Sun Yat-sen University. Univariate and multivariate analyses using the Cox regression model were performed to determine the prognostic value of AGR.
Univariate analysis suggested that AGR was a predictive factor for (overall survival) OS but not for recurrence free survival (RFS). After adjustment for other risk factors, multivariate analysis showed that AGR remained independently associated with OS. The optimal cut-off point for AGR was determined to be 1.44. Kaplan–Meier curves showed that there was a significantly lower mean survival time in the low AGR group compared to the high AGR group. A low AGR was found to be significantly associated with high alkaline phosphatase, gamma-glutamyl transpeptidase, total bilirubin levels and an advanced American Joint Committee on Cancer TNM stage, but a low hemoglobin level.
In summary, patients with higher AGRs have better outcomes than those with lower AGRs. Preoperative AGR can be a reliable marker for evaluating the prognosis of cholangiocarcinoma patients.
Abstract
We experimentally study a circuit quantum acoustodynamics system with a superconducting artificial atom coupled to both a two-dimensional surface acoustic wave resonator and a ...one-dimensional microwave transmission line. The strong coupling between the artificial atom and the acoustic wave resonator is confirmed by the observation of the vacuum Rabi splitting at the base temperature of dilution refrigerator. We show that the propagation of microwave photons in the microwave transmission line can be controlled by a few phonons in the acoustic wave resonator. Furthermore, we demonstrate the temperature effect on the measurements of the Rabi splitting and temperature induced transitions from high excited dressed states. We find that the spectrum structure of two-peak for the Rabi splitting could become into those of several peaks under some special experimental conditions, and gradually disappears with the increase of the environmental temperature
T
. The continuous quantum-to-classical crossover is observed around the crossover temperature
T
c
, which is determined via the thermal fluctuation energy
k
B
T
and the characteristic energy level spacing of the coupled system. Experimental results agree well with the theoretical simulations via the master equation of the coupled system at different effective temperatures.
The thermal expansion and thermal diffusion properties of Fe−Al alloys were measured using dilatometric and laser flash methods. At two allotropic transformation temperatures, the length change of ...the rapidly solidified pure Fe by injection casting deviates from that of the pure Fe by heating-cooling processing in a dilatometer. The ferro-/paramagnetic transition and second order transition do not influence the thermal expansion behaviors of Fe−Al alloys as temperature increases from 473 to 1373 K. The thermal expansion coefficients of Fe70Al30, Fe60Al40 and Fe55Al45 alloys are apparently larger than those of Fe25Al75 and Fe90Al10 alloys. Once temperature exceeds 877 K, the thermal expansion coefficients of Fe-Al alloys are enhanced with the increase of Al content, except for Fe25Al75 alloy owing to the large packing factor of FeAl3 crystal structure. In the temperature range from 309 to 877 K, the thermal diffusivity as a function of temperature decreases in the sequence of Fe90Al10, Fe55Al45, Fe60Al40, Fe70Al30 and Fe25Al75, and their values are lower than that of pure Fe at the same temperatures. As temperature increases, the thermal diffusivity values of Fe−Al alloys increase, except that of Fe90Al10 alloy decreases in the temperature range from 294 to 979 K and then increases once temperature further increases to 1078 K because of the ferro-/paramagnetic transition. Their thermal expansion coefficient and thermal diffusivity serve as linear or polynomial functions of temperature.
•CTE and thermal diffusivity of Fe−Al alloys were determined.•CTE of Fe70Al30, Fe60Al40 and Fe55Al45 are larger than others.•Ferro-/paramagnetic transition causes an inflexion on thermal diffusivity curve.•CTE and thermal diffusivity variations with T satisfy linear/polynomial relations.
The back-streaming neutrons (back-n) is a white neutron experimental facility at the China spallation neutron source (CSNS). The time structure of the primary proton beam makes it fully applicable to ...use the time-of-flight (TOF) method for neutron energy measuring. We implemented the electronics of TOF measurement on the general-purpose readout electronics designed for all the seven detectors in back-n. The electronics are based on the peripheral component interconnect express eXtensions for instrumentation (PXIe) platform, which is composed of field digitizer modules (FDM), trigger and clock modules (TCM), and signal conditioning modules. The T0 signal synchronous to the CSNS accelerator represents the neutron emission from the target. It is the start of the time stamp. The TCM receives, synchronizes, and distributes the T0 signal to each FDM based on the PXIe backplane bus. Meanwhile, the detector signals, after being conditioned, are fed into FDMs for waveform digitizing. The first sample point of the signal waveform is the stop of the time stamp. According to the time stamp and the time of the signal over the threshold, the total TOF can be obtained. The time-to-digital converter (TDC) based on field-programmable gate array (FPGA) is implemented on the TCM to accurately acquire the time interval between the asynchronous T0 signal and the global synchronous clock phase. There is also an FPGA-based TDC on the FDM to accurately acquire the time interval between the T0 signal arriving at the FDM and the first sample point of the signal waveform. The over-threshold time of signal is obtained offline. This method for TOF measurement is efficient and not needed for additional modules. Test results showed that the accuracy of TOF is subnanosecond and can meet the requirement for back-n at the CSNS.
Purinergic mechanisms appear to be involved in motor as well as sensory functions in the urinary bladder. ATP released from efferent nerves excites bladder smooth muscle, whereas ATP released from ...urothelial cells can activate afferent nerves and urothelial cells. In the present study, we used immunohistochemical techniques to examine the distribution of purinoceptors in the urothelium, smooth muscle, and nerves of the normal cat urinary bladder as well as possible changes in the expression of these receptors in cats with a chronic painful bladder condition termed feline interstitial cystitis (FIC) in which ATP release from the urothelium is increased. In normal cats, a range of P2X (P2X(1), P2X(2), P2X(3), P2X(4), P2X(5), P2X(6), and P2X(7)) and P2Y (P2Y(1), P2Y(2), and P2Y(4)) receptor subtypes was expressed throughout the bladder urothelium. In FIC cats, there is a marked reduction in P2X(1) and loss of P2Y(2) receptor staining. Both P2X(3) and P2Y(4) are present in nerves in normal cat bladder, and no obvious differences in staining were detected in FIC. Smooth muscle in the normal bladder did not exhibit P2Y receptor staining but did exhibit P2X (P2X(2), P2X(1)) staining. In the FIC bladder smooth muscle, there was a significant reduction in P2X(1) expression. These findings raise the possibility that purinergic mechanisms in the urothelium and bladder smooth muscle are altered in FIC cats. Because the urothelial cells appear to have a sensory function in the bladder, it is possible that the plasticity in urothelial purinergic receptors is linked with the painful bladder symptoms in IC.
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