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Arterialized and nonarterialized rat models of orthotopic liver transplantation are widely used for studying various aspects of graft function. Although bile duct damage has been implicated in graft nonarterialization, any impact on graft secretory function is unknown. This study sought to investigate whether nonarterialized orthotopic liver transplantation (NOLT) is a valid model for studying bile formation after the animal has fully recovered from the perioperative period. Twenty-four-hour bile collections were performed on eight arterialized and eight nonarterialized rats 4 weeks after transplantation to avoid the confounding effects of preservation-reperfusion injury and perioperative stress. Eight unoperated rats were used as control. There was no difference in mortality or biliary complications between the two transplant groups. The nonarterialized rats exhibited a higher serum aminotransferase level, but serum bilirubin was normal. NOLT resulted in more portal lymphocytic infiltration and bile ductular proliferation. Despite these histologic changes, bile duct epithelial cells remained intact, and spontaneous graft rearterialization was evident in the NOLT group. Bile salt secretion, pool size, and synthesis in both transplant groups did not differ from unoperated rats. NOLT did not adversely affect either bile acid-dependent or bile acid-independent flow. Biliary cholesterol secretion was markedly reduced in both transplant groups, resulting in a more favorable cholesterol saturation index. In conclusion, hepatic allograft secretory function is well maintained at 4 weeks even in the absence of hepatic arterial reanastomosis. Compensatory mechanisms possibly prevent irreversible hepatobiliary damage in NOLT. The NOLT model is quite reasonable to study bile formation after transplantation.

Altered hepatic secretory function after orthotopic liver transplantation constitutes a major perioperative clinical problem. Cholestasis and cholesterol gallstone formation are among the most frequent complications reported. Such changes in the allograft secretory function can be secondary to many factors like graft injury due to preservation and marked rejection, surgical complications, immunosuppressive therapy, and sepsis. The effects of liver transplantation per se on bile formation and biliary lipid secretion are unknown. The rat model of orthotopic liver transplantation was used to characterize better the true effect of transplantation without the influence of these confounding variables. Twenty-four-hour bile collections were performed on nine transplanted versus nine liver-denervated (sham) rats 4 weeks after surgery, and nine normal Sprague-Dawley rats. The liver allografts showed mild lymphocytic infiltration in portal tracts and the serum alanine transaminase levels were not significantly elevated. Bile flow and the secretion of bile salts and bilirubin under basal conditions were unchanged. Bile salt pool size, synthesis rate, and bile acid composition did not differ among the three groups. However, cholesterol secretion was dramatically reduced (50%) in the transplanted rats and decreased 31% in the liver-denervated rats (P < .001 and .01, respectively), resulting in a more favorable cholesterol saturation index (CSI = 0.29 for transplanted and 0.32 for sham versus 0.45 for normal controls; P < .01). Thus, liver transplantation with its attendant denervation did not impair hepatic secretory function, but rather improved biliary lipid composition despite mild rejection.

The magnetic properties and magnetocaloric effect (MCE) in RE2Cu2In (RE = Er and Tm) compounds and its composite materials have been investigated. A large reversible MCE is observed at around their own Curie temperature of T C ~ 39.4 and 31.6 K for Er2Cu2In and Tm2Cu2In, respectively. Under a magnetic field change of 0–7 T, the maximum values of magnetic entropy change () are estimated to be 18.4 and 18.2 J kg−1 K−1 for Er2Cu2In and Tm2Cu2In, respectively. A table-like MCE at a temperature of 20–50 K and enhanced refrigerant capacity (RC) are realized in the Er2Cu2In–Tm2Cu2In composite materials. For magnetic field changes of 0–5 and 0–7 T, the maximum improvements of RC reach 32% (12%) and 28% (14%), in comparison with that of the individual compound Er2Cu2In (Tm2Cu2In), respectively. The excellent MCE properties make the RE2Cu2In composite materials attractive for low-temperature magnetic refrigeration.

Test suite reduction is necessary to reduce the testing cost and increase efficiency, therefore, test suite reduction model is proposed, and test suite reduction problem is converted into a standard optimization problem. Additionally, an improved e volutionary algorithm is also proposed, which encodes the chromosome with quantum bit as its basic information bit. It achieves the individual evolution by improving the quantum rotating gates using adaptive rotation, and its convergence speed and global optimization ability is superior to the traditional evolutionary algorithm. Motivated by this, we propose a novel test suite reduction method using quantum evolutionary. Finally, experiments validate the technology with higher efficiency.

Lidar echo signal is a typical non-steady-state, non-stationary signal, and difficult to be dealt with by the traditional filtering methods. As a new signal processing theory proposed in recent years, Empirical Mode Decomposition method can adaptively divide the lidar echo signal into different intrinsic mode function (IMF) components according to different time scale, and noise mainly concentrates in the high-frequency component. However, when filtered with simply removing high frequency component, the useful signal will be possible to be reduced. In this paper, a new method which combines Empirical Mode Decomposition (EMD) with Savitzky-Golay filter is proposed. With experiments, it is indicated that our approach not only removes the noise component effectively but also maintains the useful signal, then will improve the accuracy in the next phase of data processing.

Lidar raw echo data has characteristics such as huge data quantity, strong discreteness and unpredictability. According to the construction of Lidar monitoring network of atmospheric environment, the existing network can not provide enough bandwidth to transmit Lidar data in real time. In this paper, we propose a novel hybrid lossless compression algorithm to reduce the transmission amount, namely the probability statistics lossless compression algorithm base on the improved LZW(Lempel-Ziv-Welch), which combines Huffman coding. With experiment on the raw two-value atmospheric data, we verify the effectiveness of our approach that the compression ratio is close to 9.5:1 and the coding efficiency is up to 98%.

The magnetic properties and the magnetocaloric effect (MCE) in TmZn have been studied by magnetization and heat capacity measurements. The TmZn compound exhibits a ferromagnetic state below a Curie temperature of TC = 8.4 K and processes a field-induced metamagnetic phase transition around and above TC. A giant reversible MCE was observed in TmZn. For a field change of 0–5 T, the maximum values of magnetic entropy change (−ΔSMmax) and adiabatic temperature change (ΔTadmax) are 26.9 J/kg K and 8.6 K, the corresponding values of relative cooling power and refrigerant capacity are 269 and 214 J/kg, respectively. Particularly, the values of −ΔSMmax reach 11.8 and 19.6 J/kg K for a low field change of 0–1 and 0–2 T, respectively. The present results indicate that TmZn could be a promising candidate for low temperature and low field magnetic refrigeration.

Shear fault-bend folding produces ramp anticlines with very distinctive shapes. They are characterized by long, gentle backlimbs that dip less than the fault ramp, in contrast with classical fault-bend folding. Backlimb dips and limb lengths increase progressively with fault slip, by a combination of limb rotation and kink-band migration. We summarize and apply two simple end-member theories of shear fault-bend folding involving a weak dcollement layer of finite thickness at the base of a ramp: (1) simple-shear fault-bend folding, in which the layer undergoes an externally imposed bedding-parallel simple shear with no basal fault, and (2) pure-shear fault-bend folding, in which this basal layer slides above a basal fault and shortens and thickens above the ramp, with no externally applied bed-parallel simple shear. In the limit of large displacement, the fold geometry in pregrowth strata approaches the geometry of classical fault-bend folding, with a backlimb dip that approaches the ramp dip. However, even in these cases, growth strata may record the history of limb rotation that is characteristic of a shear fault-bend fold heritage. We demonstrate that these theories are in agreement with well-imaged seismic examples from the Nankai Trough and Cascadia accretionary wedges, which show substantial shears (40–65) over stratigraphic intervals of a few hundred meters.

The pathogenesis of hepatic allograft rejection remains unclear. We aimed to clarify the early role of intercellular adhesion molecule-1 (ICAM-1)-mediated cell recruitment in chronic hepatic rejection. Liver transplantation was performed from Lewis to Lewis rats (isograft controls) and from Lewis to Brown Norway rats (allograft rejection group). The allografted rats were treated with either ICAM-1 antisense oligonucleotides (10 mg · kg−1· day−1× 6 days ip) or a control preparation (either ICAM-1 missense oligonucleotide or normal saline). Hepatic leukocyte recruitment in vivo was studied on day 6 by using intravital microscopy. Liver histology, biochemistry, and survival rates were also examined. Leukocyte adhesion in terminal hepatic venules was significantly increased in the rejection group compared with isograft controls. Antisense ICAM-1 in the allografted group effectively reduced leukocyte adhesion. Histology and liver chemistry were less deranged in the antisense-treated groups compared with control-treated allografted rats. In the allograft groups, survival was significantly prolonged in the antisense-treated rats (42.3 ± 1.2 days) compared with the controls (25.2 ± 2.7 days). These results showed that early leukocyte recruitment in the hepatic microvasculature of rejecting allografts is ICAM-1 dependent and suggest that impacting on early cell recruitment can significantly ameliorate chronic rejection.

High temperature differential scanning calorimetry (DSC) is applied to undercool and crystallize melts of a Cu70Co30 alloy into the metastable miscibility gap. The kinetic prefactor Γ and the activation energy ΔG* of the nucleation rate are determined based on the statistical analysis within classical nucleation theory. The value of Γ reaches 2.64 (0.21) × 1037 m−3 s−1, which is close to that of the value for homogenous nucleation and much larger than that of undercooled pure Co melts. The value of ΔG* is estimated to be 67 (2.5) kBT which is also higher than that of undercooled pure Co melts. The nucleation of the crystallization of the Co-rich phase is governed by homogeneous nucleation or conditions that are indistinguishable from homogeneous nucleation and the Cu-rich liquid phase effectively prevents the occurrence of heterogeneous nucleation for the nucleation of the Co-rich phase in the liquid-phase separated Cu70Co30 alloy. The results indicate that nucleation of the crystalline phase is sensitive...

A rat model of common bile duct ligation (BDL)-induced hepatic fibrosis was used to assess the expression and activities of collagen-degrading proteinases and their inhibitors during the progression of fibrosis. Expression of four members of the matrix metalloproteinase (MMP) family (MMP-2/gelatinase A, MMP-3, MMP-9/gelatinase B, and MMP-13) and three tissue inhibitors of metalloproteinases-1, -2, and -3 (TIMP-1, TIMP-2, and TIMP-3) were evaluated by Northern blot analysis of RNA from liver tissue isolated at 0, 2, 5, 10, 20, and 30 days after either a BDL or sham operation. In addition, we analyzed free gelatinase and TIMP activities by zymography and reverse zymography, respectively. We found that the proteolytic activities of MMP-2 and MMP-9 increased by 2 days after ligation, reached maximal levels at day 10, and remained high through the study period, whereas the gelatinolytic activities in plasma were unchanged. The increase in gelatinase activities was accompanied by an increase in the TIMP mRNA transcripts. TIMP-1 transcripts appeared at day 2, increased until day 10, and remained elevated throughout the study period. TIMP-2 and TIMP-3 transcripts become detectable on day 10 and remained stable afterwards. No corresponding increase in TIMP protein activity was detected by reverse zymography. This appears to result from the formation of TIMP/MMP complexes. These findings indicate a likely surplus in the BDL model of fibrosis of free gelatinases as compared with the TIMPs. Thus, excessive TIMP production is not a sufficient explanation for the observed extracellular matrix accumulation, but complex changes in the local MMP/TIMP balance may underlie the pathomechanisms of fibrosis.

Portal hypertension due to either prehepatic portal hypertension or cirrhosis is associated with cardiovascular derangement. We aimed to delineate regulatory mechanisms in the brain stem cardiovascular nuclei in rat models of prehepatic portal hypertension and cirrhosis. Neuronal activation in the nucleus of the solitary tract (NTS) and ventrolateral medulla (VLM) were assessed by immunohistochemical staining for the immediate-early gene product Fos. In the same sections, catecholaminergic neurons were counted by tyrosine hydroxylase (TH) staining. Ninety minutes after hypotensive hemorrhage (or no volume challenge), the animals were killed for Fos and TH medullary staining. These protocols were repeated after capsaicin administration. The NTS of unchallenged sham-operated rats had scant Fos-positive cells (3.6 +/- 0.4 cells/section), whereas hemorrhage significantly increased Fos staining (91.8 +/- 14). In contrast, the unchallenged portal hypertensive and cirrhotic groups showed increased Fos staining (14.3 +/- 5.8 and 32.8 +/- 2.8, respectively), which hemorrhage did not alter significantly. The numbers of TH-positive cells were similar in the three unchallenged groups; double labeling revealed that approximately 50% of TH-positive cells were activated by hemorrhage in the sham and cirrhotic rats but not the portal hypertensive rats. Similar patterns of Fos and TH staining were observed in the VLM. Capsaicin treatment not only significantly reduced the Fos-positive neuron numbers in portal hypertensive and cirrhotic rats but also attenuated hemorrhage-induced Fos and double-positive cells in both NTS and VLM. These results suggest that disordered trafficking in capsaicin-sensitive nerves and central dysregulation contribute to blunted cardiovascular responsiveness in cirrhosis and prehepatic portal hypertension.