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Chinese Fusion Engineering Test Reactor (CFETR) is a new superconducting tokamak device being designed in China, which aims at bridging the gap between ITER and DEMO, where DEMO is a tokamak demonstration fusion reactor. Two diagnostic cases, ITER-like case and towards DEMO case, have been considered for CFETR early and later operating phases, respectively. In this paper, some preliminary consideration of ITER-like case will be presented. Based on ITER diagnostic system, three versions of increased complexity and coverage of the ITER-like case diagnostic system have been developed with different goals and functions. Version A aims only machine protection and basic control. Both of version B and version C are mainly for machine protection, basic and advanced control, but version C has an increased level of redundancy necessary for improved measurements capability. The performance of these versions and needed R&D work are outlined.

To investigate hydrodynamic performance of the end cover under different inclined angles, a series of 3-Dimensional geometric models of the end cover with different inclined angles were built by Creo. The maximum inclined angle is 32 degrees and the minimum is 6 degrees. Numerical simulations by solving the Navier-Stokes equation, coupled with the "k-ɛ" turbulence model, were carried out. At last, regressive analysis method is used to deal with the result data. The data obtained by simulation were mainly analysed from three aspects. They are cause of the driving torque, drive efficiency and inclined angle of flow channel. The results show that the driving torque is formed mainly by the positive pressure of the water, and the influence of the viscous force on the driving torque of the rotor is negligible. What's more, both driving torque and pressure difference decrease with the increase of inclined angle in the form of power function. The driving efficiency increases in form of logarithmic function with the increase of inclined angle. This research has a great significance in the control of rotational speed of rotor and revealed the relationship between the driving torque of the rotor and the flow channel of the end cover.

High spin states of ${}^{112}$In were investigated using the reaction ${}^{110}$Pd(${}^{7}$Li,5$n$)${}^{112}$In at a beam energy of 50 MeV. A new level sequence has been found in this nucleus and the configuration $\ensuremath{\pi}{g}_{9/2}^{\ensuremath{-}2}{g}_{7/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}$ before the alignment and the configuation $\ensuremath{\pi}{g}_{9/2}^{\ensuremath{-}2}{g}_{7/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}^{3}$ after the alignment are assigned. The self-consistent titled axis cranking relativistic mean-field model calculations are performed to interpret the rotational structure and the characteristic features of antimagnetic rotation have been presented for the band after backbend.

High-spin states in the odd-odd ${}^{128}$I have been studied experimentally using the ${}^{124}$Sn(${}^{7}$Li, 3n$\ensuremath{\gamma}$)${}^{128}$I reaction at beam energies of 28 and 32 MeV. A level scheme built on the known ${T}_{1/2}=175$ ns, (${6}^{\ensuremath{-}})$ isomer has been established. The low-lying states in the level scheme have been proposed to be associated with the $\ensuremath{\pi}{d}_{5/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}$ and $\ensuremath{\pi}{g}_{7/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}$ two-quasiparticle excitations. The strongly populated negative-parity states, forming a bandlike structure, have been assigned to be based on the $\ensuremath{\pi}{g}_{7/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}$ configuration. The $\ensuremath{\pi}{h}_{11/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}$ multiplet ${9}^{+}$, ${10}^{+}$, and ${11}^{+}$ members have been identified according to the systematics of the corresponding level structures observed in the lighter odd-odd iodine isotopes. The two-quasiparticle configuration assignments are supported by the nucleon pair approximation and empirical shell-model calculations.

Excited states in ${}^{165}$Er have been populated using the ${}^{160}$Gd(${}^{9}$Be, 4$n$) reaction at beam energies of 42 and 45 MeV. A band consisting of two levels at excitation energies of 1317.6 and 1505.9 keV, both of which decay strongly to the $11/{2}^{\ensuremath{-}}[505]$ band, is observed and assigned as the $\ensuremath{\gamma}$-vibrational band built on the $11/{2}^{\ensuremath{-}}[505]$ configuration. In addition, a newly identified level is proposed as a three-quasiparticle state.

High-spin states in $^{161}\mathrm{Er}$ have been studied experimentally using the $^{150}\mathrm{Nd}$($^{16}\mathrm{O}$,5$\mathit{n}$) reaction at a beam energy of 86 MeV. The $5/{2}^{+}[642]$, $3/{2}^{\ensuremath{-}}[521]$, and $11/{2}^{\ensuremath{-}}[505]$ bands are extended up to high-spin states, and particularly the $\ensuremath{\alpha}=\ensuremath{-}1/2$ branch of the ground state $3/{2}^{\ensuremath{-}}[521]$ band is revised significantly. The relatively enhanced $E1$ transitions from the $3/{2}^{\ensuremath{-}}[521]$ band to the $5/{2}^{+}[642]$ band are observed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and near-prolate shape and triaxial deformation are proposed to the $3/{2}^{\ensuremath{-}}[521]$ and $5/{2}^{+}[642]$ bands, respectively. Signature inversion occurs in the $3/{2}^{\ensuremath{-}}[521]$ band after the band crossing in $^{161}\mathrm{Er}$, and the systematics of the signature inversion associated with the $3/{2}^{\ensuremath{-}}[521]$ configuration are discussed. By analyzing the properties of the relatively enhanced $E1$ transitions, it is found that the $R(E1/E2)$ values show angular momentum dependence before the band crossing, and these enhanced $E1$ transitions could be attributed to octupole softness.

Objectives: Proline‐rich inositol polyphosphate 5‐phosphatase (PIPP) is one of the signal‐modifying enzymes that play pivotal regulatory roles in PI3K signalling pathway. The aim of this study was to determine the role of PIPP in early development of fertilized mouse eggs, via inhibition of Akt activity and subsequent downstream signalling events. Materials and methods: The mRNA transcript levels of endogenous PIPP and Akt1, Akt2, Akt3 were detected in G(1), S, G(2) and M phases of fertilized mouse eggs by RT‐PCR. Levels of exogenous PIPP, phosphorylated Akt at Ser473, dephosphorylated cdc2 at Tyr15 and levels of CCNB1, were detected respectively by immunoblotting. Changes in Akt localization were observed by fluoroimmunoassay; meanwhile, changes in activity of Akt and its downstream MPF were detected. Percentages of cells undergoing division were determined by counting, using a dissecting microscope. Results: PIPP and Akt1 transcripts were detectable in G(1), S, G(2) and M phases of fertilized mouse eggs, but Akt2 and Akt3 were not. We also observed that overexpression of PIPP in fertilized eggs decreased expression of phosphorylated Akt at Ser473 and altered membrane localization of phosphorylated Akt at Ser473 specifically. Furthermore, overexpression of PIPP resulted in decreases in mitosis‐phase promoting factor activity, level of dephosphorylated cdc2 at Tyr15 and cleavage rate of fertilized mouse eggs. Conclusions: Our data suggest, for the first time, that PIPP may affect development of fertilized mouse eggs by inhibition of level of phosphorylated Akt at Ser473 and subsequent inhibition of downstream signal cascades.

Excited states of $^{118}\mathrm{Sn}$ have been populated in the $^{116}\mathrm{Cd}$($^{7}\mathrm{Li}$,$1p4n$) reaction with a beam energy of $50$ MeV. The previously known level scheme is extended in the low-spin region as well as to higher spins. The systematic behavior of the intruder deformed bands in the Sn isotopes is discussed. Total Routhian surface calculations and configuration-fixed constrained triaxial relativistic mean-field approaches are employed for analysis of the nuclear structure of $^{118}\mathrm{Sn}$.

The magnetic and chiral rotation, the critical symmetry are fundamental problems in the study of nuclear structure. Here we report the recent results from the experiments on the magnetic and electric rotations in 106Ag, the chiral rotation in 130Cs and the evolution of X(5) symmetry in 176Os.

Single crystals of Ba 1− x Sr x TiO 3 with 0.015 ⩽ x ⩽ 0.05 have been grown by Czochralski technique. The optical transmission spectrum and the photorefractive experimental results of a single-domain Ba 0.952 Sr 0.048 TiO 3 sample are reported. The effective density of empty traps N E , a lumped parameter n 3 o r eff and the response time at the total optical intensity of 1 W/cm 2 were measured by two-beam coupling experiments to be 4.7 × 10 16 cm -3 , 190 pm/V and 0.8 s, respectively. Self-pumped phase conjugation has been observed at nine wavelengths ranging from 457.9 nm to 632.8 nm. Self-pumped phase-conjugate reflectivities higher than 35% were obtained for all of the wavelengths used. The highest value is 55% reached at 514.5 nm.

High-spin states of (156)Yb have been studied via the (144)Sm((16)O,4n)(156)Yb fusion-evaporation reaction at beam energy 102 MeV. The positive-parity yrast band and negative-parity cascade have been extended up to higher-spin states, respectively. In the present work, the negative-parity sequence above the 25(-) state was found to be irregular and fragment into many parallel branches. This pattern may related to the excitation from the nucleon in the Z=64,N=82 core. The characteristics of alignment plot and E-GOS curve for the positive-parity yrast sequence in (156)Yb indicate that this nucleus may undergo an evolution from quasivibrational to quasirotational structure with increasing angular momentum. Based on a systematic summary of the available experimental alignments for the even-A (156,158,160,162,164)Yb isotopes, the structural evolutions induced by the increase in angular momentum, as well as by the change in neutron numbers, in these even-A Yb isotopes have been discussed in comparison with the cranked Woods-Saxon-Strutinsky calculations by means of total-Routhian-surface (TRS) methods.

The high spin states of 106Ag were populated via the fusion‐evaporation reaction 100Mo(11B,5n)106Ag at a beam energy of 60 MeV. A new level scheme of 106Ag is built on basis of the present experiment. The positive parity band with the configuration of πg9/2⊗V[h11/22(g7/2/d5/2)] is discussed on the ground of shears mechanism. Theoretical calculation of the effective interaction performed by TAC model agrees well with the experimental value. Systematics study shows that Ag isotopes are probably at the boundary of magnetic rotation in A∼110 mass region.

High-spin states in 86Sr have been investigated by using in-beam γ ray spectroscopy with the 82Se(9Be, 5n)86Sr reaction at a beam energy of 53 MeV. A new dipole sequence has been observed and the mixed configurations of unpaired valence nucleons and before the alignment and the configuration after the alignment are assigned respectively. Shell-model and self-consistent titled axis cranking relativistic mean-field model calculations are performed to interpret the rotational structure and the characteristic features of magnetic rotation have been presented for the sequence.

High spin states in 136,137La and 148Ce nuclei have been investigated. The new level schemes for these nuclei have been established. In 136La, observed band crossing as well as the signature splitting and inversion in πh11/2⊗νh11/2 band has been discussed. Other two bands were proposed as oblate deformation with γ ∼ −60°. In 137La, several new bands have been established. The band crossing and oblate deformation have been discussed. In 148Ce, the double octupole deformation bands with s = +1 and s = −1 have been proposed.

The high-spin states of the odd-odd nucleus $^{90}\mathrm{Nb}$ have been investigated with in-beam \ensuremath{\gamma}-spectroscopic techniques via the $^{76}\mathrm{Ge}$($^{19}\mathrm{F},5n)^{90}\mathrm{Nb}$ reaction at a beam energy of 80 MeV. $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ coincidences were measured using a $\ensuremath{\gamma}$-ray detector array. Twenty new $\ensuremath{\gamma}$ rays have been assigned to $^{90}\mathrm{Nb}$ and the level scheme has been extended up to an excitation energy of 8.095 MeV at spin $18\ensuremath{\hbar}$. The level structure of $^{90}\mathrm{Nb}$ at high spin states has been well reproduced using semiempirical shell-model calculations in the model space $\ensuremath{\pi}(1{p}_{1/2},0{f}_{5/2},0{g}_{9/2})\ensuremath{\nu}(0{g}_{9/2})$. The results show that the excitation of protons plays an important role in generating the high-spin states of $^{90}\mathrm{Nb}$.

We demonstrate a resonant cavity wavelength tunable detector with a record 30-nm continuous tuning range, 17-dB extinction ratio, and a low 7-V tuning voltage. The detector map be biased to operate in one of two modes. In the first, the detector is tuned to a specific wavelength. In the second, the detector can be tuned to a nominal wavelength and remain locked to the wavelength of the incident light despite wavelength variations. Consequently, this detector is ideal for operation as a cost-effective and robust receiver for WDM communication systems, spectroscopic applications, and wavelength measurement.

Experimental data have suggested that BM-cell implantation can improve infarcted cardiac function. However, the number of implanted cells that survive is still unknown. The present study was performed to investigate whether implantation of autologous BM mononuclear cells (BM-MNCs) transfected with phVEGF165 can increase the number of surviving implanted cells, and enhance functional improvement of infarcted hearts in rabbits.Acute myocardial infarction (AMI) in rabbits was replicated by ligating the left anterior descending coronary artery, and animals were randomly divided into the following three groups: I AMI control group (n=7); II BM-MNCs transfected with phVEGF165 implantation group (n=7); III BM-MNCs implantation group (n=7). In addition, sham-operated (n=5) rabbits were randomly selected to serve as a non-infarction control group (VI). Animals for cell implantation received intramyocardial injections of autologous BM-MNCs 14 days after AMI. Echocardiography and hemodynamic studies were performed to evaluate cardiac structure and function 28 days after implantation. The implanted sites were examined using immunofluorescence to identify the phenotypes and number of the labelled cells. Reverse transcriptase (RT)-PCR and Western blot analysis were performed to detect the expression of hVEGF165 gene and VEGF165 protein respectively.Failed cardiac function produced by AMI was significantly improved in Groups II and III 28 days after cell implantation. BM-MNCs transfected with phVEGF165 implantation conferred a further improvement of cardiac function, with significant changes of all assessed parameters when compared with BM-MNCs implantation alone (all P0.05). The implanted cells demonstrated myogenic differentiation with the expression of Troponin T and organized contractile proteins. The positive staining for Factor VIII-related Ag indicated the induction of angiogenesis in the infarct area. The percentage of Brdu-positive myocyte, endothelial cells was 75+/-%, 34.1+/-4.6% in Group II, significantly higher than that in Group III(51+/-7%, 11.3+/-2.5% respectively, P0.05). RT-PCR analysis demonstrated exclusive expression of hVEGF165 gene in Group II, and Western blot showed the expression of VEGF165 protein was significantly higher in Group II than in Group III (P0.05).Implantation of BM-MNCs transfected with phVEGF165 can increase the number of implanted cells surviving, and enhance the impaired cardiac function after AMI.

Multiple-wavelength vertical-cavity surface-emitting laser (VCSEL) arrays are fabricated using a location-resolvable in situ optical calibration method and a patterned-substrate growth technique in a molecular beam epitaxy (MBE) system. The high and low wavelength limits are achieved within 0.28% accuracy and with a 2.66 A wavelength standard deviation from 4 × 35 arrays.

The purpose of this study was to define the temporal trend in body temperature of patients during the first 5 days after total hip arthroplasty (THA). The medical records of 98 consecutive THAs were reviewed, 88 clinically uncomplicated cases were included. The average maximum temperature reached during the study period was 38.08 degrees C, a 3.7% (Por =.01) increase from the preoperative base line of 36.64 degrees C. In this study, 62.5% of patients reached a temperatureor =38.0 degrees C; 19.3%or = 38.5 degrees C; and 3.4%or = 39.0 degrees C. No patients had a preoperative temperature ofor =38 degrees C recorded. On the first postoperative day, 39 patients had a temperatureor =38 degrees C. The number of febrile patients progressively decreased until by the fifth postoperative day, only 5 patients had a temperatureor =38 degrees C recorded.

We report the first low threshold, buried heterostructure (BH) vertical cavity surface emitting laser (VCSEL) using organometallic chemical vapor deposition regrowth. Very low threshold current of 0.8 mA and threshold current density of 490 A/cm2 are achieved with 8 and 32 μm diam BH VCSELs, respectively. Both 8 and 16 μm diam BH VCSELs emit a single TEM00 fundamental mode for current levels many times thresholds. Most single‐mode emissions are linearly polarized with a predetermined direction in the [011] crystal orientation.

Combining the new spectroscopy results of 144 Tb and previous spectroscopy studies of neighboring nuclei, a systematic investigation on the low-lying spectra in N = 78 ~ 80 isotones is performed. Good systematics have been found for the coupling patterns which couple the odd nucleon(s), such as πh11/2, [Formula: see text], to the 2+, 4+, 6+ and 3- core excitations. It is found that the relative excitation energies of the states formed by coupling h11/2 proton(s) to the 2+, 4+ core excitations are pushed up, in contrast with those formed by coupling h11/2 neutron hole(s) to the 2+, 4+ core excitations, which are pulled down. According to the systematics, the interpretation that the 17/2+ states observed in 141 Sm and 143 Gd are the fully aligned member of coupling the odd h11/2 neutron hole to the octupole 3- core excitation, is explored to the isotones 145 Dy , 142 Eu , and 144 Tb .

To observe the effect of allitridi on the expression of proliferating cell nuclear antigen (PCNA) of cultured rabbit aortic smooth muscle cell (SMC).The expression of PCNA was examined with immunohistochemical technique (LSAB method) and the contents of superoxide dismutase (SOD), lipid peroxide (LPO), prostacyclin (PGI2) and cyclic adenosine monophosphate (cAMP) in medium were simultaneously determined.Allitridi has the effects of increasing SOD activity, decreasing LPO, elevating PGI2 and cAMP, reducing the expression of PCNA (all P0.05-0.01).Allitridi could inhibit SMC proliferation.

Reticulocytosis in rats was induced by repetitive bleeding. Both in the vitro and the in vivo studies showed that the detected reductive speed of methemoglobin of the bleeding group was faster than that of the control group at all time intervals. At the same time, the NADH-cytochrome b5 methemoglobin reductase activity and the molybdenum content in erythrocytes of the bleeding group were significantly increased. Regressional analysis showed that there was a significantly positive correlation between the enzyme activity and the molybdenum content. It is proposed that molybdenum might be required for the enzyme activity.

Vertical cavity surface emitting lasers (VCSELs) and resonant cavity detectors are of great interest for optical communications applications. In order to obtain high performance devices with high yield, the epilayer thickness and growth rate must be controlled to within ±1.5 %. Conventional molecular beam epitaxy calibration method such as reflection high energy electron diffraction (RHEED) and ion-gauge beam flux measurements are limited to an accuracy of a few percent. To achieve higher accuracy, various in situ optical techniques have been investigated for growth rate calibration [l]-[2] and for real time growth control [3]-[4]. The former is desirable because of its versatility and cost-effectiveness.

Twenty patients undergoing open-heart valvular operations were divided randomly into two groups. Intermittent perfusion of cold crystalloid (St. Thomas Hospital solution) with hypothermic cardiopulmonary bypass (CPB) in the hypothermic group and continuous administration of warm blood cardioplegia with normothermic CPB in the normothermic group were used respectively. The results of warm blood cardioplegia were superior to those of cold crystalloid. 70% of patients treated with the warm technique had spontaneous return of normal sinus rhythm shortly after removal of the aortic cross-clamp, compared with only 10% of the hypothermic group (P0.05). The extracorporeal support time from releasing of aortic clamp to the weaning of CPB was significantly shorter in the normothermic group (33.50 +/- 3.78 min vs. 25.00 +/- 4.64 min, P0.05). The postoperative ventilation support time was also much shorter than that of the hypothermic group (19.84 +/- 1.11 h vs. 38.98 +/- 16.55 h, P0.05). More atrial beating occurred in the normothermic group (80% vs. 20%, P0.05) during aortic clamping, and it is showed that continuous warm blood cardioplegia might not efficiently prevent the atrium from damage.

An improved technique for bloodless hepatic resection using in vivo isolation and asanguinous hypothermic perfusion was described to deal with the huge liver tumour involving the liver hilum, the main hepatic veins and retrohepatic inferior vena cava. The original Fortner's technique was modified, including the incision; isolated cold perfusion of the healthy half of the liver through the portal vein; suprahepatic outlet for the perfusate, and shortened hepatic ischemia time by perfusing hepatic artery prior to the repair or reconstruction of the portal vein. Using this technique, two huge liver tumors were successfully resected, and the indications, intraoperative monitoring and early postoperative courses were discussed.

Lifetimes of excited states above 10+ in the yrast band in 176Os have been measured using the Doppler shift attenuation method, via the fusion evaporation reaction . Lifetimes of states over 12+ were measured for the first time. The deduced transitional quadruple moments (Qt), together with the previous data using a recoil distance method, are compared with theoretical calculations based on the X(5) model and the interaction boson model. For the states below spin 10+, the data of previous work support an X(5)-like structure, but for the states above 10+, the value of Qt remains almost constant, being the characteristic of a symmetric rotor. The present result suggests that the shape of the nucleus 176Os changes from X(5) critical-point symmetry to an axially deformed rotor with increasing spin.

Through many years' research, a set of cultivation techniques for Rehmannia glutinosa in summer has been found out as "selecting necks in autumn; growing seedlings with plastic films in early spring; culturing around summer solstice and reaping after autumn". A Study has also been made on the scope feasible for spreading the application of these techniques.

An improved technique for bloodless hepatic resection using in situ isolation and asanguinous hypothermic perfusion was described to deal with huge liver tumors involved in the liver hilum, the main hepatic veins and retrohepatic inferior vena cava. The original Fortner's technique was modified, including the choice of incision; semi-isolated perfusion of the liver portion preserved through the single portal vein; suprahepatic outlet of the perfusate and the shortening of the period of hepatic ischemia by reperfusion of hepatic artery prior to the repair or reconstruction of the portal vein. The initial successful experience of the technique applied to 2 pediatric cases with giant liver tumors was reported, and the indications, intraoperative and early postoperative courses were discussed.

The high-spin states of 140Pm have been investigated through the reaction 126Te(19F, 5n) at a beam energy of 90 MeV. A previous level scheme based on the 8− isomer has been updated with spin up to 23 . A total of 22 new levels and 41 new transitions were identified. Six collective bands were observed. Five of them were expanded or re-constructed, and one of them was newly identified. The systematic signature splitting and inversion of the yrast πh11/2⊗νh11/2 band in Pr and Pm odd–odd isotopes has been discussed. Based on the systematic comparison, two ΔI = 2 bands were proposed as double-decoupled bands; other two bands with strong ΔI = 1 M1 transitions inside the bands were suggested as oblate bands with γ ~ −60°; another band with large signature splitting has been proposed with oblate-triaxial deformation with γ ~ −90°. The characteristics for these bands have been discussed.

All nitrogen-fixing legume root nodules resulting from infection by symbiotic Rhizobium contain leghemoglobin. Leghemoglobin facilitates and regulates the flow of oxygen to the nitrogen-fixing bacteroids, resulting in creating the microaerobic environment necessary for the nitrogenase activity (Wittenberg et al. 1972; 1974; Wittenberg 1976). Leghemoglobins from soybean (Appleby et al. 1975; Ellfolk 1960), kidney bean (Lehtovaara et al. 1974), yellow lupine (Broughton et al. 1972; Kuranova et al. 1976), serradella (Broughton et al. 1972), broad bean (Richadson et al. 1975), snake bean (Broughton et al. 1971), Seshania (Bogusz et al. 1987; Gu et al. 1989), which form large round nodules, and from pea (Lehtovaara et al. 1980), clover (Thulborn et al. 1979), alfalfa (Jing et al. 1982, 1983a; Lullien et al. 1987), which form elongated nodules with terminal meristems, have been purified and studied.

The nucleus of a blastula cell from Tilapia (Oreochromis nilotica, family Cichlidae, order Perciformes) was transplanted into an enucleated egg of Loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes). From among 3747 nucleo-cytoplasmic hybrid (NCH) eggs two NCH larval fish (0.05%) were obtained; one died on the 6th day and the other died on the 12th day after the operation. Morphological examinations showed that both NCH larval fish had developed normally with an opened mouth except they could not take food after complete utilization of their egg yolk on the 5th day of development. The possible mechanisms for obtaining such inter-order NCH larval fish are discussed. This is the first report indicating that inter-order NCH larval fish can be obtained in spite of their evolutionary divergence.

Teleosts from different families and orders were used as materials for nuclear transplantation experiments. (1) The nuclei of goldfish (Carassius auratus, family Cyprinidae, order Cypriniformes) were transplanted into the enucleated egg cytoplasm of loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes) and vice-versa. (2) The nuclei of Tilapia (oreochromis nilotica, order Perciformes) were transplanted into the enucleated egg cytoplasm of goldfish (Carassius auratus, order Cypriniformes). The chromosome number of the nucleus donor fish is different from that of the cytoplasmic recipient fish in each of the two combinations. In the first case, only a few early nucleo-cytoplasmic hybrid (NCH) larval fish were obtained in each combination. In second case, even though a high percentage of NCH blastulas were also obtained, the majority of them died at the same developmental stage, except a few which survived until early gastrula stage. The examination of the metaphase chromosome figures of the NCH blastulas or embryos obtained in all three combinations indicated that they were of nucleus-donor type. The developmental rates of all the NCH eggs were similar to those of cytoplasmic-recipient type. Scanning electronmicroscopy examination showed that the morphology of NCH blastula cells, which were obtained from the combination of Tilapia nucleus and goldfish cytoplasm, manifested obviously abnormal features and the cells were arrested at different stages of cell disintegration. Two-dimension polyacrylamide gel electrophoretograms of the homogenates of Tilapia, goldfish and their NCH blastula cells showed that the protein synthetic pattern of NCH blastula was similar to that of Tilapia nucleus type. The results of experiments which failed to obtain NCH adult fish in all three combinations can be explained as a result of developmental incompatibility between the donor nucleus and the enucleated recipient egg cytoplasm, which were from distantly related fish species. And the chromosome numbers of all the component fish of the three combinations which were examined in the experiment and shown to be quite different from each other in the tested fish, should not be overlooked as one of the essential factors causing the developmental incompatibility in NCH fish in this experiment.

The structural gene coding for human growth hormone (hGH) was fused to the promoter of the mouse gene for metallothionein-1. These fusion genes were introduced into pronuclei of the fertilized eggs of mice by micro-injection. We have injected MT-hGH genes into 121 mouse eggs which were transferred into the oviducts of eleven pseudo-mothers. Seven out of eleven mothers gave birth. Forty-three litters were born. These litters were grown-up and their tails were cut for isolating the DNA. The DNA of each mouse was examined by dot hybridization and Southern blotting. We found that eighteen mice had incorporated the fusion genes and grew larger than control mice. Synthesis of human growth hormone was induced further by zinc, which normally induces metallothionein gene expression. We also isolated the RNA from the livers of transgenic mice. The RNA was hybridized with hGH gene. It showed that on the transcription level the hGH gene was transcribed into mRNA in the transgenic mice. Using the same method to examine the second and third generation of the transgenic mice, we found that the incorporated gene could be inherited for generations. But the body-weight of transgenic mice appeared to decrease in the progeny. The offspring obtained from different combinations of parents (carrying or not carrying hGH gene) were different.

Polarisation and modal behaviour are compared for very low threshold oxide confined and airgap confined vertical cavity lasers. Although both structures have nearly identical optical models leading to the same stable fundamental mode emission up to many times threshold, they show very different polarisation behaviours. Predetermined polarisation up to 18 times threshold is achieved for the oxide confined vertical cavity lasers.

A tunable vertical cavity surface emitting laser with a record 15 nm wavelength tuning for an applied voltage of only 5.7 V is reported. Both red and blue shift are obtained. The device uses a micromachined cantilever to freely suspend a portion of the upper mirror reflector. The cantilever may be electrostatically deflected towards the substrate, to tune the resonant wavelength of the laser microcavity.

Summary form only given. The authors report buried heterostructure (BH) vertical cavity surface emitting lasers (VCSELs) emitting a single TEM/sub 00/ mode with a predetermined polarization and low-threshold currents. A threshold current of 0.8 mA and a record-low threshold-density of 490 A/cm/sup 2/ have been achieved with 8 and 32 mu m diameter lasers, respectively. The VCSEL heterostructure used includes three InGaAs strained quantum wells, and 15 and 20.5 pairs of GaAs-AlAs as the top and bottom Bragg reflectors, respectively, grown by molecular beam epitaxy. The threshold currents of 8, 16, and 32 mu m BH VCSELs are 0.8, 1.2, and 3.5 mA, respectively. Both the 8 and 16 mu m BH VCSELs emit a single TEM/sub 00/ mode up to four to five times threshold. The emission is linearly polarized in a predetermined direction. The stable single-mode behavior is attributed to the combination of index-guiding in the active region and anti-index-guiding in the Bragg reflectors. >