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In the present study, we analyzed quantitative aspects of earthworms alongside soil and climate factors in three habitats, which include corn farms, vegetable fields, and grassland, in Northern China. Eighteen earthworm species belonging to seven genera and three families were found across habitat types in 57 plots. Amynthas modiglianii and Aporrectodea caliginosa trapezoides were the dominant species across the three habitat types. The average density of earthworms among the habitat types was 74.39 individuals/m2 with the vegetable fields having the highest density. The highest number of earthworm species was found on the corn farms. The vegetable fields were found to have the highest Shannon–Wiener (H' = 1.64) and Margalef (D = 1.06) indices. Species composition was similar among the vegetable fields but differed significantly in the corn farms. Most soil samples from collection sites were alkalescent. Temperature and vapor pressure were positively correlated with earthworm species diversity and abundance, but negatively correlated with species dominance. Elevation was negatively correlated with species diversity and abundance, but positively correlated with dominance. Some soil and precipitation factors showed non-significant correlations with species diversity. In addition, there was no significant correlation between the distribution ratio of juveniles and environmental factors. [ABSTRACT FROM AUTHOR]

Bi2Sr2CaCu2Ox (Bi-2212) single-filamentary and multi-filamentary wires were fabricated by powder in tube (PIT) process and sintered under the over pressure heat treatment (OPHT) process. The thermal behavior, microstructure, phase composition, and superconducting properties of wires were characterized by thermal gravimetric analysis, scanning electron microscopy, X-ray diffraction, and four-probe method, respectively. The inclined grain microstructure and randomly orientated grains were observed directly in single-filamentary wire. The performance of Bi-2212 mono-filamentary wire was extremely lowered than that of multi-filamentary wire, which could be ascribed to poor microstructure and texture. The inhomogeneous melting behavior of single-filamentary wire was responsible to the poor microstructure and the randomly orientated grains. Furthermore, high engineering critical current density (Je) of 1224 A/mm2 and critical current density (Jc) of 4896 A/mm2 were obtained in 666-filament Bi-2212 wire with good grain orientation and microstructure. It revealed that the grain orientation might be a major current-limiting factor. Therefore, the multi-filamentary architecture with good texture was critical for the improvement of performance Bi-2212 wires during OPHT process. [ABSTRACT FROM AUTHOR]

Peanut (Arachis hypogaea L.) is a geocarpic plant, which absorbs nutrients not only through roots but also through pods. However, the effect of nitrogen fertilizer application in pod area on pod gene expression and peanut yield is unknown. In this study, we determined the pod yield, dry matter accumulation, nitrogen accumulation in different organs under different nitrogen treatment in root zone and pod zone. The results showed that pod area application of nitrogen led to significantly higher pod yield to compare with the control. The application of 60 kg/hm2 nitrogen at the pod area led to the highest pod yield, full fruit rate and plant nitrogen content. 15N directly absorbed by pods was mainly accumulated in the shell at early stage of pods development, and then transferred to seeds at later period. However, the ratio of 15N absorbed directly by pods from soil was low, only about 10%. To understand the underlying molecular mechanisms, immature pods of different developmental stages were collected for gene expression analysis. The expression levels of several genes encoding ABC type transporter family, nitrate reductase, nitrite reductase and glutamine synthetase increased in different stages of pod development upon pod area nitrogen application. These results indicated that the efficiency of N assimilation and glutamate metabolic cycle in pods was increased under pod nitrogen application. The expression levels of several genes in gibberellin and brassinolide biosynthesis pathways were also up-regulated, suggesting that these two hormones were involved in the promoting effect of pod nitrogen application on pod growth. [ABSTRACT FROM AUTHOR]

A novel method is presented for the production of the 6 + 1 filament MgB2 wires using internal Mg diffusion (IMD) process. For the MgB2 long wire with 1.4-mm diameter produced by graphene-coated Nb addition, the critical current (Ic) is about 1000 A at 4 T and 4.2 K, which is 2.5 times higher than that of the undoped sample. The increased Ic is attributed to the enhanced flux pinning force and improved grain connectivity. The obtained results show that graphene-coated Nb addition MgB2 wires have excellent superconductivity and mechanical property compared with the conventional PIT wires in practical application. [ABSTRACT FROM AUTHOR]

During gene transformation, selection makers are important for efficient screening of the transgenic lines. The commonly used selection marker genes in plants such as neo, bar and hpt confer antibiotics resistance or herbicide resistance to the transgenic lines, which may have uncertain effects on environment and biosafety. Other selection marker genes with non-toxic products such as xylose isomerase, phosphomannose isomerase and β-glucuronidase are exogenous genes and may also have side effects on transgenic plants. Hence, endogenous and safe marker genes are desirable. Here, a new vector designated pCAMBIA2300-35S-OCS-AhFAD2B was constructed, in which the NeoR gene was replaced by AhFAD2B gene as a reporter gene. FAD2B catalyzes the formation of linoleic acid from oleic acid. High oleic acid peanut (Arachis hypogaea L.) (oleic acid content is >70% of the total fatty acids) variety Kainong1715 was used for transformation by Agrobacteriumtumefaciens injection through peanut calyx tube. A total of 688 seeds were harvested, and the oleic acid content of each seed was measured using near infrared reflectance spectroscopy (NIRS). The oleic acid content of 93 seeds was found to be less than 70% indicating that these seeds had been transformed. Further validation by PCR amplification demonstrated that these seeds were true transgenic seeds. AhFAD2B as a reporter gene in peanut could greatly improve screening efficiency of transgenic seeds using NIRS. In addition, linoleic acid, the catalytic product of AhFAD2B, is the essential fatty acid for human health. This is the first report on the development of marker using endogenous gene in peanut. [ABSTRACT FROM AUTHOR]

The finite element model of a tubular member under the combined action of axial compression, creep, and axial impact was constructed with the numerical analysis software, to evaluate the core concrete creep effect on the dynamic responses of a steel tubular member in axial compression. In the model, the creep effect of core concrete of different age is equivalent to the change of its elastic modulus. Then, the dynamic responses of a tubular member in axial compression and impact were simulated considering the creep effect, time-history curves of impact load, contact time, axial deformation, stress and strain were plotted, and the effect of creep on them was discussed. The impact load peak decreases with the development of the core concrete creep, and the most is about 51%; the contact time and axial deformation increase; the concrete stress decreases, but the concrete strain increases greatly. The minimum and maximum principal concrete strains after 30 years exceeded those after 28 days by 6.35 and 8.6 times, respectively. The core concrete creep has a less effects on the stress and strain of the steel tube. The fruits provide a scientific help for the impact resistance design of a concrete-filled steel tubular member in axial compression. [ABSTRACT FROM AUTHOR]

Bi-2212 wires, which have high critical current density and critical magnetic field without anisotropy, offer significant potential applications for ultrahigh-field superconducting magnets. The Bi-2212 wire is very sensitive to strain. The strands are inevitably subjected to cyclic thermal or electromagnetic stress during application. There is a lack of understanding regarding the fatigue properties. In this paper, the degradation behavior of critical current for Bi-2212 wires under axial tensile fatigue loading was investigated. It was found that the fatigue life decreases with the increase in maximum fatigue stress. [ABSTRACT FROM AUTHOR]

MgB2 bulks with graphene doping were synthesized by high energy ball milling process. The effect of high energy ball milling and graphene doping on the microstructure and critical current density of MgB2 was studied systematically. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and physical property measurement system (PPMS), respectively. The densities of ball-milled graphene-doped samples were larger than those of pure samples. The superconducting properties of MgB2 could be increased by the high energy ball milling process, in comparison with the sample prepared by grinding process. Moreover, the significant improvement of superconducting properties for ball-milled MgB2 samples could be achieved with the addition of graphene. The combination of graphene doping and suitable ball milling could refine the grain and improve the inter-grain connectivity of MgB2. MgB2 with 3 at% graphene doping prepared by high energy ball milling with 2 h exhibited very high critical current density of 6.4 × 105 A/cm2 at 20 K and 0 T. [ABSTRACT FROM AUTHOR]

The effect of graphene (G) coated Si, Ti and Nb additions on the superconducting properties of MgB2 was systematically studied. The additives were prepared by a coating process and all introduced powders were scattered and combined with graphene. The coating process was useful for the uniform distribution of additives in MgB2 samples. The additives could effectively make the refinement of MgB2 grain size, which achieved an enhancement of surface pinning. Meanwhile, the densities of all the doped samples were larger than those of pure samples, which ensured a better intergrain connection for supercurrent. Therefore, the critical current density of MgB2 with 8 wt% G coated Nb addition got a significant enhancement due to the improvement of grain connectivity and flux pinning properties. [ABSTRACT FROM AUTHOR]

Rice seed storability is an important characteristic of seed quality so that the cultivars with strong seed storability are expected in the production of hybrid seeds. Presently, little is known about the genetic and physiological mechanisms controlling rice seed storability. In this study, a double haploid population derived from the cross between a japonica cultivar CJ06 and an indica cultivar TN1 was used to identify the quantitative trait loci (QTLs) for seed germination percentage (GP) and fatty acid content (FA) during natural storage or artificial aging. A total of 19 QTLs, including ten QTLs for GP and nine QTLs for FA, were identified on nine chromosomes with the phenotypic variations ranged from 2.1 to 22.7%. Besides, six and three pairs of epistatic interactions were identified for GP and FA, respectively. Moreover, qGP-9, a QTL for germination percentage, was delimited in an interval of 92.8 kb between two STS markers P6 and P8, which contains 15 putative open reading frames. These results provide important information for understanding the genetic mechanisms on rice seed storability, and will be useful for breeding new rice varieties with high seed storability. [ABSTRACT FROM AUTHOR]

Summary: We used an osteopenic adult ovariectomized (OVX) rat model to evaluate various sequential treatments for osteoporosis, using FDA-approved agents with complementary tissue-level mechanisms of action. Sequential treatment for 3 months each with alendronate (Aln), followed by PTH, followed by resumption of Aln, created the highest trabecular bone mass, best microarchitecture, and highest bone strength. Introduction: Individual agents used to treat human osteoporosis reduce fracture risk by ∼50-60 %. As agents that act with complementary mechanisms are available, sequential therapies that mix antiresorptive and anabolic agents could improve fracture risk reduction, when compared with monotherapies. Methods: We evaluated bone mass, bone microarchitecture, and bone strength in adult OVX, osteopenic rats, during different sequences of vehicle (Veh), parathyroid hormone (PTH), Aln, or raloxifene (Ral) in three 90- day treatment periods, over 9 months. Differences among groups were evaluated. The interrelationships of bone mass and microarchitecture endpoints and their relationship to bone strength were studied. Results: Estrogen deficiency caused bone loss. OVX rats treated with Aln monotherapy had significantly better bone mass, microarchitecture, and bone strength than untreated OVX rats. Rats treated with an Aln drug holiday had bone mass and microarchitecture similar to the Aln monotherapy group but with significantly lower bone strength. PTH-treated rats had markedly higher bone endpoints, but all were lost after PTH withdrawal without follow-up treatment. Rats treated with PTH followed by Aln had better bone endpoints than those treated with Aln monotherapy, PTH monotherapy, or an Aln holiday. Rats treated initially with Aln or Ral, then switched to PTH, also had better bone endpoints, than monotherapy treatment. Rats treated with Aln, then PTH, and returned to Aln had the highest values for all endpoints. Conclusion: Our data indicate that antiresorptive therapy can be coupled with an anabolic agent, to produce and maintain better bone mass, microarchitecture, and strength than can be achieved with any monotherapy. [ABSTRACT FROM AUTHOR]

We have studied the growth behavior of pyrochlore structure LaZrO (LZO) thin films with different thickness on biaxial texture NiW substrates prepared by metal-organic deposition (MOD) method. The structure and morphology of LZO films were investigated by x-ray diffraction (XRD) and scanning electron microscopy (SEM). Our results show that the surface morphology of LZO films varies with changes in the surface coverage ratio of the metal substrates after crystallization in argon-hydrogen atmosphere. The degree of texture of the LZO films reaches a maximum when the film thickness increases to 37 nm, where the NiW substrate surface is just fully covered. The complete coverage of the substrate surface together with the enhanced texture suggests that there exists a possible connection between the surface morphology and the texture development of the films prepared by MOD. Information on the nucleation and growth of oxide thin films on metal substrates with biaxial texture is important for understanding the mechanism of buffer layer formation and also for optimizing the preparation conditions for high-temperature superconducting coated conductors. [ABSTRACT FROM AUTHOR]

This paper presents our recent activities for the development of low-loss Bi2223 tapes with interfilamentary oxide barriers. In order to suppress the side effect on Bi2223 phase formation during sintering process, SrZrO was selected as barrier materials. Moreover, small amount of Bi2212 was mixed with SrZrO to improve their ductility for cold working. By controlling coating thickness of oxide barriers before stacking, reducing a tape width below 3 mm and careful twisting of the filaments with its length below 5 mm, coupling frequency f exceeded 250 Hz even in an AC perpendicular magnetic field. Critical current densities J of tightly twisted barrier tapes were ranged in 12-14 kA/cm at 77 K and self-field, which was 25% lower than the nontwisted one (=18 kA/cm). To our knowledge, this is the first result to achieve both J>12 kA/cm and f>250 Hz simultaneously for Bi2223 tapes in an isolated state. These twisted barrier tapes showed 60-70% lower perpendicular field losses than a conventional 4 mm-width tape with fully coupled filaments at 50 mT and 50 Hz. [ABSTRACT FROM AUTHOR]

La2Zr2O7 (LZO) formation of bulk powders and of films by chemical solution deposition (CSD) process have been studied using propionates. The treatment involved a one step cycle in the reducing forming gas (Ar-5%H2) to be compatible with Ni-5at%W RABITS. Large amount of residual carbon was found in LZO powders formed in these conditions (10 wt%). The volume fraction of the cube texture in LZO films on Ni-5at%W RABITS was found to be a function of the speed of the gas flown above sample. This phenomenon is discussed in considering the C deposited from the carbon-containing gases emitted during the pyrolysis of the precursor. Using proper conditions (950 °C and the speed of gas of 6.8 × 10−2 m/s), LZO films with good surface crystallinity could be obtained on Ni-5at%W RABITS as demonstrated by X-ray diffraction, electron backscattered diffraction and RHEED. The existence of residual carbon in oxide films is a common question to films deposited by CSD processes under reducing condition. [ABSTRACT FROM AUTHOR]

Background. Retrosigmoid vestibular neurectomy is suggested to be the most effective and safe procedure to control intractable vertigo associated with Ménière’s disease. The purpose of this study is to report the excellent efficacy of vertigo control, the good preservation of hearing, the rare complications and the simplicity of retrosigmoid vestibular neurectomy performed by an interdisciplinary team of neurosurgery and otorhinolaryngology experts of our teaching hospital. Methods. Seventy-three patients with Ménière’s disease who were refractory to medication or other surgical therapy were consecutively operated on over a period of 7 years. All the patients were referred to the senior author (CSL) for the surgery and were followed-up by the same neurootologist (JTL). The retrosigmoid approach for selective vestibular neurectomy was the only surgical method used in our neurosurgical facility. During surgery the separation line was made just at the cochleo-vestibular cleavage plane on the cochlear nerve to achieve a more complete sectioning of the vestibular fibres. To ensure accurate and complete data collection, patient data was prospectively entered into an electronic database, which was used subsequently for analysis of vertigo control, preservation of hearing, improvement in functional levels, and surgical complications. Results. Long-term excellent and good vertigo control were achieved in 69 (94.5%) and 4 (5.5%) patients respectively. Hearing was preserved to within 10 dB of the pre-operative pure-tone thresholds in 91.8% of patients at 1 month after the surgery. The functional levels improved to level 1 by a reduction of 3–5 points and became stabilised by 2 years of follow-up in all of our patients. No patient was worse post-operatively. Complications were uncommon and included superficial wound infection and transient partial facial paralysis in one patient each. Total hearing loss did not occur post-operatively. The mean operating time was 70 min. Conclusion. Selective vestibular neurectomy via the retrosigmoid approach is an effective and simple neurosurgical procedure for the control of intractable vertigo in Ménière’s disease while preserving hearing. [ABSTRACT FROM AUTHOR]

A radiation dose lower than what had previously been recommended was given to a case of intrasellar germinoma in a 17-year-old patient who suffered from migraine-like headache for 2 years, amenorrhoea for 3 months and a body-weight loss of 10 kg over 4 months. Baseline assessment of pituitary hormone reserve was within the lower limits of the normal range, except for an elevated serum prolactin level (PRL). Magnetic resonance imaging (MRI) showed an abnormal, slightly enhanced mass in the pituitary fossa, extending along the pituitary stalk and to the hypothalamus. Transsphenoidal removal of the intrasellar part of the tumour was performed and microscopic sections of the surgical specimens revealed a pure germinoma. Adjunctive radiation therapy (RT) was given 3 weeks after surgery. A total dose of only 27 Gy was delivered to this patient. The patient’s menstrual cycles resumed in 4 months. Repeated MRI follow-up showed no recurrence of the tumour. [ABSTRACT FROM AUTHOR]

Background: To delineate the epidemiologic trend, clinical characteristics and therapeutic outcomes of bacterial meningitis in young adults in southern Taiwan. Patients and Methods: Over a period of 18 years, 329 cases of culture-proven adult bacterial meningitis were identified at our hospital. Among these 329 cases, 62 were identified as young adults (≥ 40 years) and their clinical features, laboratory data and therapeutic outcomes were reviewed. The prognostic factors between fatal and non-fatal groups were compared. Results: The 62 young adults were 48 men and 14 women, aged 17–40 years. Thirty of the 62 patients belonged to nosocomial infection, and the other 32 belonged to community-acquired infection. A total of 74% (46/62) of the patients had a postneurosurgical state as the underlying condition. Alcoholism (n = 8) was the most common underlying condition of the other 16 patients with spontaneous meningitis. Of these 62 patients, Klebsiella pneumoniae (12) and Pseudomonas aeruginosa (9) were the most common implicated gram-negative pathogens. During the late study period, there was an increase in coagulase-negative staphylococcus and Staphylococcus aureus infections. The therapeutic results of this group of patients are as follows: 13 patients died, 18 had full recovery and 31 had varying degrees of neurologic deficits. Impaired consciousness and thrombocytopenia were significant prognostic factors. Conclusion: A postneurosurgical state is an important preceding event for young adults to develop bacterial meningitis. Of the implicated gram-negative pathogens, K. pneumoniae and P. aeruginosa are common; however, there has been an increase in staphylococcal infection in recent years. Therapeutic results of this specific group of patients showed that 20% (13/62) of the patients died, and 50% (31/61) of the patients in this study had neurologic deficits. However, the small case number and possible bias of case selection has limited the analytical conclusions of this study. Further large-scale studies are needed to delineate the clinical characteristics and therapeutic outcomes of bacterial meningitis in this specific group of patients. [ABSTRACT FROM AUTHOR]

Background. The precise course of resolution of postoperative residual HFS after a single MVD has not been well categorised quantitatively in the literature. Not all patients with HFS were cured immediately after a single MVD; some of them exhibited a gradual disappearance of the HFS over a period of time. The time course of the gradual resolution of HFS is categorised and the situation of re-exploration in a few patients whose HFS persisted or recurred is determined. Methods. The results of 547 MVDs in 545 Chinese patients were reviewed using the database from the author’s personal records between January 1992 and December 2002. Different outcomes were observed and divided into four categories according to the variable convalescent period: type 1, spasm cured immediately; type 2, spasm persisted with milder severity and faded away gradually from 7 days to as long as 2 years; type 3, spasm ceased immediately but recurred after 3 days and ran the same course as in type 2; type 4, failed. Findings. Four hundred and seventy-nine patients followed a type 1 course, which constituted an 87.9% immediate success rate. Forty-one patients (7.5%) followed a type 2 course, including three whose spasm persisted for more than 2 years. Twenty-three patients (4.2%), including one with venous compression, followed a type 3 course with their spasm ceased within three months. All of them had typical vascular loop compression. Another patient with a venous contact failed to respond positively to the first MVD underwent re-operation within 2 months. Re-operation was also performed in one patient four days after the first MVD due to persisting and even more severe spasm. These two patients were categorized type 4 as they failed the first MVD (0.4%). Late recurrence was noted in five patients from 1 to 2 years after the first MVD, only one of whom underwent re-exploration and was then cured again. Conclusions. Approximately 80% of the patients with HFS achieved immediate excellent results after a single MVD, the rest of the patients exhibited residual but usually milder spasms, which resolved gradually over a period of time. According to the patterns of the residual or persisting spasms, the situation and timing of re-exploration can be determined without difficulty. The surgeon should be concerned about missing the responsible vessels in patients with typical HFS who completely failed the first MVD. [ABSTRACT FROM AUTHOR]

During 2000 to 2001, a total of 73 blubber samples from 13 species of stranded or accidentally captured cetaceans were collected from Taiwan coastal waters for polychlorinated biphenyl (PCB) analysis. After homogenization, saponification, liquid-liquid extraction, and silica-gel solid-phase extraction, PCB concentrations were determined by gas chromatography/mass spectrometry. Total concentrations of 19 PCB congeners (ΣPCBs) were between 0.23 µg/g lipid weight of Risso's dolphin to 33.73 µg/g lipid weight of rough-toothed dolphin. Pentachlorobiphenyls, hexachlorobiphenyls and heptachlorobiphenyls were the predominant PCB congeners species. PCB153 was the most abundant congener in all samples. The PCB153/IPCBs consistently comprised between 20% to 30% of all congeners. The toxicity measured as 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) were from 2.7 pg/g lipid weight of finless porpoise to 2,900 pg/g lipid weight of rough-toothed dolphin. PCB 118, a mono-ortho congener, was the largest contributor to TEQs. PCB concentrations and TEQs were higher in mature male than in immature male animals but were inconsistent in female animals because of a possible transferring of PCBs from maternal cetaceans to their off-springs during gestation and lactation. Stranded cetaceans had significantly higher PCB levels than by-catch cetaceans because of their higher lipid consumption during starvation or illness. From the collected samples, we also found that cetaceans from Taiwan waters had relatively lower PCB concentrations and TEQs than those from high-latitude areas. [ABSTRACT FROM AUTHOR]

The article discusses the study regarding the evaluation of low-dosage environmental mutagens with a long-term, cultured epithelial cell line. According to sources, Benzanthracene (BaA) and Benzopyrene (BaP) are major unsubstituted polycyclic or polynuclear aromatic hydrocarbons identified by the U.S. Environmental Protection Agency as priority pollutants. In a concentration of 10 mg/ml, BaA and BaP were dissolved in cyclohexane, and in order to have the right test concentrations of BaP and BaA for the mutagenicity experiments, preliminary cytotoxicity assays were performed. Thus, based from the experiments conducted, preliminary range-finding cytotoxicity assays were conducted in order to prevent the cytotoxic effects of the tested compounds.