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The China Dark Matter Experiment reports results on light WIMP dark matter searches at the China Jinping Underground Laboratory with a germanium detector array with a total mass of 20 g. The physics threshold achieved is 177 eVee ("ee" represents electron equivalent energy) at 50% signal efficiency. With 0.784 kg-days of data, exclusion region on spin-independent coupling with the nucleon is derived, improving over our earlier bounds at WIMP mass less than 4.6 GeV. [ABSTRACT FROM AUTHOR]

A firm, poorly circumscribed soft tissue tumor occurred in the frontal and occipital or temporal musculature of four mature dogs aged 7-12 years. Radiographically, many nodular or stippled densities were scattered throughout the soft tissue mass, and the cranial bones were eroded. The tumor was characterized by nodular aggregations of proliferating chondrocytes surrounded by calcified matrix or chondroid ground substance. The intervening stroma was fibrous. These infiltrating fibrous lesions with calcified metaplastic cartilage have not been reported previously in the dog and are similar to calcifying aponeurotic fibroma in man.

Adenocarcinomas of the olfactory glands were diagnosed in five dogs. The tumors had invaded the adjacent olfactory and prefrontal areas of the cerebral hemispheres. The masses consisted of large sheets of neoplastic epithelial cells separated by connective tissue stroma. In some areas there were hemorrhage and necrosis. The anterior parts of the cerebral hemispheres had been destroyed by the invasive neoplastic cells, and the white matter in the areas was very edematous. Review of the medical and veterinary literature yielded no description of tumors originating in the olfactory glands.

Twenty-two cases of intestinal adenocarcinoma were diagnosed in an 11-year survey of 3145 feline necropsies. Histologically, tumors were grouped into four classes: (1) carcinoma with solid groups of cells, (2) adenocarcinoma with solid and acinar cells, (3) papillary adenocarcinoma, and (4) mucinous adenocarcinoma. Tumors were commonest in the ileum. Connective tissue, as well as epithelial metaplasia, were associated more often in this group of intestinal adenocarcinomas than seen before. Hypertrophy and hyperplasia of muscular layers of the unaffected sections of intestines were seen in most of the small bowel and in half of the large bowel carcinomas in this series.

An 8-year-old male Irish Terrier dog and a male St. Bernard dog each had a thyroid medullary carcinoma. The first dog was hypocalcemic before removal and with recurrence of the neoplasm. In both dogs the neoplasms were bilateral and microscopic metastases were seen only in the regional lymph nodes. Both neoplasms were characterized by a solid alveolar pattern separated by thin vascular stroma or a linear festoon-like arrangement with thick stroma. The neoplastic cells varied little and were polygonal or round with abundant pale eosinophilic and finely granular cytoplasm. There was little mitotic activity. Both carcinomas contained amyloid. Electron microscopically, the neoplastic cells had moderate nuclear pleomorphism, well developed Golgi complexes, and characteristic membrane-bound electron-dense secretory granules. In some sections, the secretory granule membranes were fused to the cytoplasmic membrane and the granules were in the extracellular space. In one carcinoma there were linear fibrillar structures with an average width of 7.8 nanometers similar to that of amyloid fibrils.

A series of Fe-C-X and Fe-C-X1-X2alloys in which X, X1and X2either raise or depress the activity of C inywere investigated by autodilatometer, optical microscopy, and transmission electron microscopy (TEM) to reveal the relations among the chemical composition, transformation kinetics, and morphology of ferrite plates. The incubation time of austenite decomposition at the nose temperature in the time-temperature-transformation (TTT) diagrams, the concentration of C in y in contact with theα/gg boundary, and the growth rate of ferrite were evaluated to estimate the magnitude of the solute drag-like effect (SDLE) for the different alloying elements used. All the results are consistent qualitatively with the SDLE hypothesis.

Repair of UV-irradiated bacteriophage in Escherichia coli by Weigle reactivation requires functional recA+ and umuD+C+ genes. When the cells were UV irradiated, the groE heat shock gene products, GroES and GroEL, were needed for at least 50% of the Weigle reactivation of the single-stranded DNA phage S13. Because of repression of the umuDC and recA genes, Weigle reactivation is normally blocked by the lexA3(Ind-) mutation (which creates a noncleavable LexA protein), but it was restored by a combination of a high-copy-number umuD+C+ plasmid and a UV dose that increases groE expression. Maximal reactivation was achieved by elevated amounts of the Umu proteins, which was accomplished in part by UV-induced expression of the groE genes. By increasing the number of copies of the umuD+C+ genes, up to 50% of the normal amount of reactivation of S13 was achieved in an unirradiated recA+ host.

The overall kinetics of the isothermal transformation of austenite to ferrite and bainite at intermediate temperatures and the microstructure of the transformation products in Fe-C-Ti, Fe-C-Ti-Si, Fe-C-Ti-Mn, and Fe-C-Ti-Mn-Si alloys were investigated with dilatometry, quantitative metallography, and TEM. The rate of transformation of austenite is retarded and the precipitation of carbide is inhibited in Ti-containing alloys by additions of Si, Mn, or Si + Mn. In addition to bainite and degenerate ferrite plates, a large amount of granular structure consisting of martensite and retained austenite (so-called granular bainite) is observed in these alloys if the isothermal reaction time is not long enough to complete austenite decomposition. It is suggested that the inhibiting effect of Si on carbide precipitation, the segregation of carbideforming elements to prior γ grain boundaries and interphase interfaces, and the enhancing effect of Si on the segregation of these elements lead to the results obtained. The results also support the view that so-called granular bainite is a mixture of transformation products produced by the partial decomposition of austenite.

Twenty-eight recA mutants, isolated after spontaneous mutagenesis generated by the combined action of RecA1202(Prtc) and UmuDC proteins, were characterized and sequenced. The mutations are intragenic suppressors of the recA1202 allele and were detected by the reduced coprotease activity of the gene product. Twenty distinct mutation sites were found, among which two mutations, recA1620 (V-275-->D) and recA1631 (I-284-->N), were mapped in the C-terminal portion of the interfilament contact region (IFCR) in the RecA crystal. An interaction of this region with the part of the IFCR in which the recA1202 mutation (Q-184-->K) is mapped could occur only intermolecularly. Thus, altered IFCR and the likely resulting change in interfilament association appear to be important aspects of the formation of a constitutively active RecA coprotease. This observation is consistent with the filament-bundle theory (R. M. Story, I. T. Weber, and T. A. Steitz, Nature (London) 335:318-325, 1992). Furthermore, we found that among the 20 suppressor mutations, 3 missense mutations that lead to recombination-defective (Rec-) phenotypes also mapped in the IFCR, suggesting that the IFCR, with its putative function in interfilament association, is required for the recombinase activity of RecA. We propose that RecA-DNA complexes may form bundles analogous to the RecA bundles (lacking DNA) described by Story et al. and that these RecA-DNA bundles play a role in homologous recombination.

We measured the kinetics of growth and mutagenesis of UV-irradiated DNA of phages S13 and lambda that were undergoing SOS repair; the kinetics strongly suggest that most of SOS mutagenesis arises from the deamination of cytosine in cyclobutane pyrimidine dimers, producing C----T transitions. This occurs because the SOS mechanism bypasses T--T dimers promptly, while bypass of cytosine-containing dimers is delayed long enough for deamination to occur. The mutations are thus primarily the product of a faithful mechanism of lesion bypass by a DNA polymerase and are not, as had been generally thought, the product of an error-prone mechanism. All of these observations are explained by the A-rule, which is that adenine nucleotides are inserted noninstructionally opposite DNA lesions.

The overall kinetics of the isothermal transformation of austenite to bainite and to pearlite in high-purity Fe-C-3 at. pct X alloys (X = Mn, Si, Ni, or Cu) containing 0.1 wt pct C and 0.4 wt pct C were investigated with quantitative metallography and transmission electron microscopy (TEM) to ascertain the presence or absence of the incomplete reaction phenomenon. The incomplete transformation of austenite to bainite was not observed in the Fe-C-Si, Fe-C-Ni, Fe-C-Cu, or Fe-0.4C-Mn alloys. It was found, however, in the Fe-0.1C-Mn alloy. Transmission electron microscopy results indicate that sympathetic nucleation of ferrite without carbide precipitation is a necessary but not a sufficient condition for the development of the incomplete reaction phenomenon. Transformation resumes following stasis in the low-carbon Fe-C-Mn alloy with the formation of a nodular bainite. The results support the view that the incomplete transformation of austenite to bainite is a characteristic of specific alloying elements and is not an inherent trait of the bainite reaction.

Five Fe-C-Si-Mn alloys were investigated by dilatometry, optical microscopy, and transmission electron microscopy (TEM) analysis to determine the effects of Si and Mn content and austenitizing temperatures on the kinetics of bainite transformation. Segregation of Mn at prior austenite grain boundaries at a temperature below Bswas detected by the scanning transmission electron microscopy + energy dispersive spectroscopy (STEM + EDS) and secondary ion mass spectroscopy (SIMS) techniques. The fraction of intragranular ferrite increases with Mn content. The time needed for the initiation of the bainite transformation tends to decrease as the austenitizing temperature decreases. The results obtained were compared with those from Fe-0.38C-1.73Si and Fe-0.38C-3.11Mn alloys. Equilibrium and nonequilibrium segregation of Mn at prior austenite grain boundaries and the effect of the interaction between Si and Mn on the segregation of Mn are used to explain the results obtained and the large difference between the kinetics of the two ternary alloys and those of the Fe-C-Si-Mn alloys.

Erythromycin is the drug of choice for treatment of Mycoplasma pneumoniae infections due to its susceptibility to low levels of this antibiotic. After exposure of susceptible strains to erythromycin in vitro and in vivo, mutants resistant to erythromycin and other macrolides were isolated. Their phenotypes have been characterized, but the genetic basis for resistance has never been determined. We isolated two resistant mutants (M129-ER1 and M129-ER2) by growing M. pneumoniae M129 on agar containing different amounts of erythromycin. In broth dilution tests both strains displayed resistance to high levels of several macrolide-lincosamide-streptogramin B (MLS) antibiotics. In binding studies, ribosomes isolated from the resistant strains exhibited significantly lower affinity for [14C]erythromycin than did ribosomes from the M129 parent strain. Sequencing of DNA amplified from the region of the 2S rRNA gene encoding domain V revealed an A-to-G transition in the central loop at position 2063 of M129-ER1 and a similar A-to-G transition at position 2064 in M129-ER2. Transitions at homologous locations in the 23S rRNA from other organisms have been shown to result in resistance to MLS antibiotics. Thus, MLS-like resistance can occur in M. pneumoniae as the result of point mutations in the 23S rRNA gene which reduce the affinity of these antibiotics for the ribosome. Since they involve only single-base changes, development of resistance to erythromycin in vivo by these mechanisms could be relatively frequent event.

Chromophobe adenoma was diagnosed in the pituitary gland of an 11-year-old domestic shorthaired cat. Histologically, the tumor consisted of a mass of cells with scant sinusoidal arrangement and connective tissue stroma and few blood vessels. In areas the neoplastic cells contained large vacuoles that occupied the entire cytoplasm and pushed the nuclei aside.

Abstract:  A 6-month-old male monkey with rickets was found dead by its keeper. Radiographic studies showed osteopenia of the entire skeletal system, a cup-shaped concavity and poor mineralization of metaphyseal ends, and markedly widened and irregular epiphyseal growth plates of the long bones and ribs. Gross anatomic findings included bowing abnormalities and microfractures in the radius, ulna, tibia, and fibia, and enlarged and widened cartilage columns extending into the metaphyses in the long bones and ribs. Histologic features included deficient mineralization and irregular disordered columns of proliferating cartilage in growth plates extending into other zones, dilated vascular channels, and poor mineralization of chondroid and osteoid tissues.

We report the results of searches for solar axions and galactic dark matter axions or axionlike particles with the CDEX-1 experiment at the China Jinping Underground Laboratory, using 335.6 kg days of data from a p-type point-contact germanium detector. The data are compatible with the background model, and no excess signals are observed. Limits of solar axions on the model-independent coupling gAe<2.5×10-11 from Compton, bremsstrahlung, atomic-recombination, and deexcitation channels and gANeff×gAe<6.4×10-17 from a 57Fe M1 transition at 90% confidence level are derived. Within the framework of the Dine-Fischler-Srednicki-Zhitnitskiy and Kim-Shifman-Vainshtein-Zakharov models, our results exclude the axion mass heavier than 0.9 and 177 eV/c², respectively. The derived constraints for dark matter axions below 1 keV improve over the previous results. [ABSTRACT FROM AUTHOR]

Distillers dried grains with solubles (DDGS) from corn contain relatively large amounts of polyunsaturated fatty acids and some yeast components, which may increase oxidative stress and alter immune function, respectively, when fed to broilers. Therefore, the study was undertaken to assess the effects of distillers dried grains with soluble (DDGS) on broilers under immunosuppressive challenge. One-day-old male broiler chickens (300) were assigned to 2 treatments with 6 replicates pretreatment. Birds were fed diets formulated to contain 0, 15% corn-based DDGS, respectively. The experimental diets were fed for 6 weeks in 2 phases. On day 21, serum IgA, IgG content and malondialdehyde (MDA), glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD), and total antioxidant activity (T-AOC) capacity were analyzed. Chickens were then randomly allotted to 1 of 4 treatment groups: negative control (NC) corn-soybean meal diet without dexamethasone (DEX) challenge, positive control (PC) corn-soybean meal diet with (DEX) challenge, 15% DDGS without DEX challenge (D), 15% DDGS with DEX (D+DEX). Based on these results, dietary DDGS did not influence ADG, ADFI and F:G of 21 d, 28 d and 42 d chicks (P > 0.05), however, DEX affected ADG and F:G of 28 d chicks remarkably (P < 0.05). Relative weights of liver, abdominal fat, spleen, thymus, and bursa were influenced by DEX challenge on d 28 (P < 0.05). DDGS reduced serum T-AOC, T-SOD, whereas increased IgA, IgG and MDA of 21-day-old broilers significantly (P < 0.05). Dietary DDGS also reduced liver T-SOD of 21-day-old broilers significantly (P < 0.05). Based on real-time PCR, 28 d chicks fed DDGS had a greater relative abundance of mRNA encoding IL-4 and IL-6 (P < 0.05), whereas DEX decreased the expression of GPX, IL-6, IL-10 (P < 0.05). Thus, 15% dietary DDGS inclusion has the beneficial effects on immune functions for broilers to some degree.

Photo-electrochemical reduction of carbon dioxide on the porous films dispersed with self-organized TiO2 nanotubes has been investigated in this work. The porous films were prepared by anodizing a titanium sheet in the electrolyte containing fluoride. Post annealing at 450 oC for 1 h, the crystal of the film turned from amorphous to anatase. The film was dipped in 1 M nitrate solution of Ag(I), Cu(II) and Fe(III), respectively, dried and irradiated by UV-light to load different impurity. Electrochemical tests including cyclic voltammetry (CV), potentiostatic reduction and electrochemical impedance spectroscopy (EIS) were conducted to estimate the catalytic activity of the films. The catalytic activity is higher for the films after compared with the as-anodized films. The catalytic activity of the porous film was enhanced with loading different impurities. The activity increases in the order: load-free < Ag-loaded < Cu-loaded < Fe-loaded films.

In order to demonstrate the feasibility of porous TiO2 multi-layers we address the possibility of color tuning of single thin films by means of varying the electrochemical anodization conditions (voltage and time). Ellipsometric data analysis using Bruggeman effective medium approximation confirms the interferometric nature of the sample color.

An attempt was made to produce immune complex vasculitis in piglets, hoping to produce as an experimental Coronary Artery Disease (CAD) animal model by administrating foreign protein, mimicking Kawasaki Disease (KD). Systemic type III hypersensitivity reaction by horse serum injection with clinical implication to CAD in KD was reported only in rabbits. Our study group consisted 22 pure bred male piglets of 1.5, 2 and 3 months of age. They were divided into control group (n=6) receiving 2 doses of intravenous normal saline, and test group A (n=8), receiving 2 doses at 10 days interval of virus and mycoplasma negative gamma globulin free horse serum (HS), 2.6gm (5ml) and 5.2gm (10ml) protein/Kg body weight, respectively, test group B (n=8) received 3 doses at 5 days interval of HS, 5.2gm protein/Kg body weight. Blood samples were collected for white blood cells, platelets, vascular endothelial growth factor, liver enzymes, cholesterol and haptoglobin. Both the test groups developed rashes, echocardiographic coronary artery dilatation and histopathological changes, whereas none of the control group developed immunopathological response. All the animals were sacrificed for the histopathological, and immuno histochemistry study at different dates after the second HS injection. There were asymmetric inflammatory coronary arteritis, such as intimal proliferation, necrosis, vacuolisation, smooth muscle cells proliferation and oedematous changes in arterial walls. The piglets, which received at 5 days interval of 3 doses of HS, manifested more skin rashes and histopathological changes in the coronary arteries than those received two doses at 10 days interval. Serum sickness is a prototype of immune complex vasculitis, it is concluded that swine may serve as an experimental model for CAD mimicking KD, for testing the efficacy of pharmacologic therapies.