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Doppler radio tracking data from Tianwen-1, China’s first Mars mission, could contribute to a better estimate of the gravity field of Phobos. In this study, we show that a determination up to degree and order 3 is feasible by considering five additional flybys of Phobos by the Tianwen-1 spacecraft, in addition to the previous flybys already done by the Mars Express spacecraft, and probably degree and order 5 is within reach. Three cases of mass repartition are considered: (i) a homogeneous case, (ii) a core-dominated Phobos, and (iii) a mantle-dominated Phobos. The case of a mantle-dominated Phobos is the easiest to detect, followed by a homogeneous Phobos, and finally by a core-dominated Phobos. We also discuss implications about the modelling of the internal structure of Phobos.

In view of the problems of low solar energy utilization efficiency, drying efficiency to be improved and sludge adhesion in the process of solar drying sludge, the research was carried out on the heat collection effect of solar collectors, sludge drying characteristics and sludge drying process, as well as the influence of sludge drying process parameters on the sludge drying rate such as hot air temperature, solar radiation intensity and air substitution,. on the self-built industrial simulation test bench. The results show that: the maximum temperature difference between the inside and the outdoor environment of the solar collectors is 36°C, when the outdoor environment temperature of the developed solar collectors is 13-26°C; the optimum process parameters of sludge drying rate under the experimental conditions that the moisture content of wet sludge is 82.7%, are as follows: the temperature of hot air is 43°C, the maximum solar radiation intensity (about 12:00), the optimal flow rate of air is controlled at 1.2m/s, the thickness of the material layer is 3cm, the large contact between air and materials improves the problem of sludge adhesion. All which provide a theoretical basis for the implementation on the industrialization of solar drying sludge.

In industrial processing, a centrifugal pump is mostly used reversely as the micro-hydraulic turbine for its lower cost. In some application situation, the working fluid will contain a part of gas which will reduce the efficiency, stability, and the power output of the machine. Due to the lower efficiency and stability of the pump as turbine (PAT) working with liquid flow, the working characteristic will deteriorate furtherly when the working fluid contains gas. Therefore, a micro-hydraulic turbine based on Francis turbine model is designed and proposed to except to obtain good performance under two-phase flow working condition. In this study, the three-dimensional transient two-phase flow model which adapts the k-ω model as turbulence model and Eulerian-Eulerian model as two-phase flow model with the commercial code ANSYS-CFX was established and solved to study the two-phase flow characteristics of the micro-hydraulic turbine with fixed guide vane openings under different gas volume fraction (GVF). The numerical simulation results show that the power, efficiency and torque of the turbine decrease with GVF. Due to the expansion of the gas in working fluid, the velocity of fluid increases with the gas, which leads to the bigger lower pressure area near the exit of the impeller. The vortex at the back of the blade is also intensified when the gas fraction increase. When the GVF is larger than 10%, the gas distribution is inhomogeneous, and most of them gather at the back side of the blade near the exit of the impeller where the GVF can reach 90%. The efficiency of the micro-hydraulic turbine is about 60% when the GVF is 20%, which needs to be improved in the future.

To investigate the liver pathological characteristics and the clearance rate of hepatitis B surface antigen (HBsAg) with antiviral treatment for 1 to 7 years old children with heptitis B e antigen(HBeAg)-negative chronic hepatitis B.A total of 49 cases with HBeAg-negative chronic hepatitis B were treated with interferon (IFN) or IFN treatment for 6 months added with lamivudine, and were followed up for at least 6 months.Retrospective analysis was performed on the liver pathological characteristics, the efficacy of antivirus treatment and its influencing factors of the HBsAg clearance rate in the cases from June 2006 to December 2013 in the 302 Hospital of People's Liberation Army.The χ(2) test was used to compare the rates.(1)The median age of cases was 3 years old(1-7 years old), 38 children were male(78%). Cases in the age group 1-2,2 -3,3 -4,4-5,5-6 and6-7 were 7, 8, 14, 6, 6 and 8 respectively. HBsAg was 100% positive in mother of the cases. (2)There were 7 children whose pre-treatment alanine aminotransferase (ALT) were ≤80 U/L and pre-treatment ALT200 U/L in 25 children. There were 24 children whose pre-treatment HBVDNA ≥1×10(7) U/ml. Genetype analysis was detected in 43 children, 3 children were B genotype, 38 were C genotype, 2 were B and C genotype. (3)Liver biopsy was performed in all children. The degree of liver inflammation ≥2 was seen in 48 (98%) children.Severe liver fibrosis and cirrhosis were found in 21(43%) children. (4)In the age group 1-2,2-3,3-4,4-5,5-6 and6-7 years old , the clearance of HBsAg was 5, 6, 2, 1, 0 and 0 respectively. The HBsAg clearance rate between 1-3 years old group and 3-7 years old group has significant difference ((73%(11/15) vs. 9%(3/34), χ(2)=18.180, P=0.000). (5)The clearance of HBsAg in male group was 11, but 3 in female group.It showed no significant difference between two groups (χ(2)=0.073, P=0.787). (6) The clearance rate of HBsAg were 0, 24%(4/17) and 40%(10/25) in the groups of pre-treatment ALT ≤80 U/L, 80ALT≤200 U/L and ALT200 U/L, respectively. There were no significant difference between the groups of ALT≤200 U/L and ALT200 U/L(χ(2)=2.223, P=0.136). In the groups with pre-treatment HBV DNA1×10(7)U/ml and HBV DNA≥1×10(7)U/ml, the clearance rate of HBsAg was 28%(7/25) and 29%(7/24). There were no significant elifference between two groups(χ(2)=0.008, P=0.928). (7)The clearance rate of HBsAg was 33%(7/21) in children with severe liver fibrosis and cirrhosis, while 25%(7/28) in children who had no severe liver fibrosis and cirrhosis.There were no significant difference between two groups(χ(2)=0.408, P=0.523).There are obvious liver injuries and severe liver fibrosis in 1-7 years old children with HBeAg-negative chronic hepatitis B. The HBsAg clearance rate in the children with antiviral treatment correlated with age, among those who received antiviral treatment before 3 years old, the HBsAg clearance rate is relatively higher.

Using first-principles calculation we investigated the structural, electronic and elastic properties of paramagnetic CaFeAs2. Our results indicated that the density of states (DOS) was dominated predominantly by Fe-3[Formula: see text] states at Fermi levels, and stronger hybridization exists between As1 and As1 atoms. Three hole pockets are formed at [Formula: see text] and Z points, and two electronic pockets are formed at A and E points. The Dirac cone-like bands appear near B and D points. For the first time we calculated the elastic properties and found that CaFeAs2 is a mechanically stable and moderately hard material, it has elastic anisotropy and brittleness, which agrees well with the bonding picture and the calculation of Debye temperature ([Formula: see text]).

Mechanical and electronic properties of Cu2Sb-type compounds MFeAs (M = Cu, Li, and Na) have been studied by the first-principles calculations. The main trends in structure parameters, mechanical parameters, electronic bands, and densities of states (DOS) for MFeAs are analyzed according to the variable cation M sites. Our results show that the lattice constants increase, while the bulk modulus, shear modulus, and Young's modulus decrease with the increasing radii of M sites in the sequence CuFeAs → LiFeAs → NaFeAs. Mulliken overlap population indicates that different M atoms in MFeAs (M = Cu, Li, and Na) would influence the bond nature of Fe-As, which may induce the superconductivity. The disappearance of the hole-pockets affects the superconductivity in CuFeAs. Although the value of the DOSs N(EF) at the Fermi level grows with decreasing radii of M sites, it is not the only factor influencing the superconductivity. Due to the repulsive interaction between Cu-3d and Fe-3d states in CuFeAs phase, it would...

From 1966 to 1989, we performed free toe transfer for thumb and finger reconstruction in 300 patients, with 286 survivals and 14 failures, a total survival rate of 95.55 percent. Follow-up for 2 to 23 years showed that movement and sensation of the reconstructed thumbs and fingers were satisfactory in all of the 286 cases. The optimal indications for the operation were defect of the thumb at the plane of the metacarpophalangeal joint and defects of the second to fifth fingers. Besides atraumatic isolation of the second toe and sophisticated microsurgical suturing technique, special attention was paid to intraoperative vascular variations, to providing the double arterial blood supply system if necessary, and to the identification and management of postoperative circulatory crisis.

Of the 25 cases of entrapment, or compression syndrome of the posterior interosseous nerve of the forearm reported, 23 were treated surgically. The compressing or entrapping factors found during the operations consisted of 14 sites in tendinous tissues, 12 in vessels, 6 in scar adhesions, and 3 unclear. Of 11 cases each had 2 or more compression sites. 19 patients underwent local decompression. And 4 cases had membranous and degenerated nerves resection and end-to-end anastomoses. Hypertrophy and inflammation appeared to be the main pathological changes in 10 cases. The causes and pathology are discussed and the early diagnosis and treatment emphasized.

From 1966 to 1989, we performed free toe transfer for thumb and finger reconstruction in 300 patients, with 286 survivals and 14 failures, a total survival rate of 95.55 percent. Follow-up for 2 to 23 years showed that movement and sensation of the reconstructed thumbs and fingers were satisfactory in all of the 286 cases. The optimal indications for the operation were defect of the thumb at the plane of the metacarpophalangeal joint and defects of the second to fifth fingers. Besides atraumatic isolation of the second toe and sophisticated microsurgical suturing technique, special attention was paid to intraoperative vascular variations, to providing the double arterial blood supply system if necessary, and to the identification and management of postoperative circulatory crisis.

The authors had designed cervical root nerve transfer from the contralateral normal side for the treatment of brachial plexus root avulsions in August 1986. Since then, the operation was performed in 50 cases. Follow-up studies showed that resection of C-7 root from the healthy side produced no long-term ill effect except numbness and pain of the fingers and weakness of gripping strength shortly after the procedure. In 10 recipient nerves of 9 cases with follow-ups of more than 2 years, satisfactory results were seen in 7. This is a new approach for the treatment of persistent cases of brachial plexus avulsion.

Superficial and internal-structure of human and rat tendons were investigated under scanning electronic microscopy. Histologically, there are many pores on the synovium, under which a layer of network of fiber bands wraps the tendon. The synovial fluid propulsion system includes: Synovium----pores----network of fiber bands----space of tendon bands----space of tendon fibers. The synovial fluid is propelled through the above structure. The function of the network structure is like a sponge, it has the function of nutrition, absorption of heat, and lubrication.

240 Wistar rats were divided into 3 groups to study the postoperative activity of smooth muscle of the anastomosed vessel and the response of it to mechanical and chemical (nor-adrenaline) stimuli, together with the changes of Ca(++)-ATPase following transplantation of the severed limb. The results showed that the post-operative circulatory crisis could set in 3 definite periods with different causes: (1) paralytic period: Within the first 48 hours after operation, no vascular spasm could be provoked anyhow. Should circulatory crisis be found, thrombosis is the most likely cause and prompt surgical exploration with appropriate management is mandatory. (2) Hypersensitive period: 49 to 96 hours after operation, following re-establishment of circulation, the smooth muscle of the vessel, having been recovering in function and in ultrastructure from pathological changes, retains its contractability; while Ca(++)-ATPase, a vascular relaxator, has not yet resumed to be active; the vessel becomes hypersensitive to stimuli of any kind. In case of circulatory crisis, vessel spasm is probably the rule. Conservative management with anti-spasmodic drugs is the treatment of choice. (3) recovery period: 97 to 240 hours after operation, both the anatomical structure and biological activity of the smooth muscle have returned normal and, the Ca(++)-ATPase has also come to play. So that the smooth muscle of vessel resumes its normal function and becomes relatively stable. However, possibility of vascular spasm exists until the tenth post-operative day has passed.

Twenty-one patients, under 6 years of age, with root avulsion of the brachial plexus were treated from 1975 to 1987. Among them, 9 had root avulsion of the upper trunk, 2 root avulsion of the lower trunk with middle trunk broken, and 10 root avulsion of the whole brachial plexus. Follow-up of 16 patients showed excellent results in 2 patients, good in 11, fair in 1 and poor in 2. It is suggested that good results can be obtained if multi-paired nerve transfer is adopted in treatment. We conclude that owing to anatomical and physiological characteristics of the respiratory system in children, it is harmful to perform phrenic nerve transfer concomitantly with intercostal nerve transfer. Advisably, two-stage operation is required, otherwise dyspnea and pneumonia are liable to occur. In addition, the time of the operation could be extended to 4-5 years after injury in children, but best results are obtained if the operation is performed within 1 year.

The authors report the observations by TEM of morbid nerve segment from 3 cases of typical neurocausalgia. It was discovered that a lot of collagen fibrils proliferation, myelin sheaths compressed partly or completely disintegrated and exposed axons. A great number of no myelinic nerve fibers, remained and a great number of macrophages were present, which are morphological characteristics of neurocausalgia.

14141 Background: Human pancreatic cancer is a devastating disease. Standard therapy, gemcitabine, is not able to alter the natural history of the disease. Targeting intracellular signaling molecules has proven to be a powerful approach in cancer therapy. Protein kinase C (PKC) family has been implicated in many human cancers including pancreatic cancer. Methods: In this pre-clinical study, we evaluated the effect of a novel small molecule inhibitor, enzastaurin, for PKCβ on human pancreatic cancer cells. We utilized MTT assay to assess cell proliferation and viability. To evaluate cell transforming activity, soft agar colony forming assay was used. Results: We showed that with addition of 20μM enzastaurin into the culture, the proliferative growth of two pancreatic cancer cell lines, Panc1 and L3.6p1, was significantly attenuated, as measured by the MTT assay. In addition, the combination of enzastaurin and a low dose of gemcitabine (25 nM) resulted in a synergistic cytotoxic effect in L3.6p1 cells. Further, the in vitro tumorogenicity assay demonstrated that the L3.6p1 cells treated with enzastaurin (20μM) formed much smaller colonies than the control parental cells in 0.4% soft-agar. Consistent with the in vitro cell proliferation results, the combination of enzastaurin and the low concentration of gemcitabine (25nM) further reduced the numbers and sizes of colonies in the soft-agar. Conclusions: Collectively, our data indicate that enzastaurin can effectively suppress the proliferation and in vitro transforming activity of the pancreatic cells, and more effectively when applied in combination with the low dose of gemcitabine. No significant financial relationships to disclose.

A system of ordinary differential equations is said to be a reversible system if there exists an involution such that the vector field is reversed under this involution. The steady-state systems of reaction-diffusion systems (RD-systems) on 1-dimensional space are all reversible ODE systems provided the kinetic terms do not involve the derivatives of component functions. If, in addition, a RD-system exhibits Z (2)-symmetry, then the Z (2)-symmetry introduces an additional involution to its steady-state system. We are interested in how this additional symmetry property affects the temporal stability and pattern of the bifurcating steady states in such RD-systems. We study the class of RD-systems whose steady-state systems are reversible with respect to two linear involutions whose product is a reversal symmetry. The set of fixed points of these involutions are both 2-dimensional planes in the 4-dimensional state space. They intersect at the constant steady states where bifurcating steady states emanate from. The steady states being studied are periodic solutions bifurcated from a constant steady state at 1 : 1 resonance in the steady-state system. Their temporal stability is analyzed through a center manifold reduction on the RD-system. A complete description of their spatial structure is also obtained. Two models, the Lambda-Omega system and a predator-prey model, are studied as examples. We conclude that all small-amplitude bifurcating steady states are temporally stable in the Lambda-Omega system and unstable in the predator-prey model. Numerical approximations of bifurcating steady states in these two models, obtained by solving both the RD-system and the steady-state system, are presented as numerical verification of our analysis. We also conclude that the bifurcation regime near 1:1 resonance in the steady-state system of the predator-prey model is hyperbolic.

A new combined measure of nerve transfer, including antebrachial medial cutaneous nerve, and free musculocutaneous flap transfer was applied to the treatment of irreversible avulsion of the brachial plexus. 12 patients underwent this operation for restoring elbow and finger flexion. Good result was obtained in 71% for elbow and 60% for finger flexion restoration. The definition of irreversible avulsion and the methods, key points and value of the operation are described and discussed in detail.

In 1985, we applied an arterialized vein stem free flap in 4 cases with success in 3. In making this flap the superficial vein with the covered skin of the limb was used. In operation the flap was inverted and the 2 ends of the vein stem were anastomosed with the artery of the recipient area. Rapid arterial blood flow not only provided blood supply to the flap, but through the "venous network shunt" and "tidal pressure difference of artery" maintained blood circulation of the flap. The details of technique and the changes of blood circulation after flap transfer are described, as are indications advantages and mechanism of blood circulation of the flap, and factors affecting the circulation.