Underlying factors determining grain morphologies in high-strength titanium alloys processed by additive manufacturing.

In recent research, additions of solute to Ti and some Ti-based alloys have been employed to produce equiaxed microstructures when processing these materials using additive manufacturing. The present study develops a computational scheme for guiding the selection of such alloying additions, and the minimum amounts required, to effect the columnar to equiaxed microstructural transition. We put forward two physical mechanisms that may produce this transition; the first and more commonly discussed is based on growth restriction factors, and the second on the increased freezing range effected by the alloying addition coupled with the imposed rapid cooling rates associated with AM techniques. We show in the research described here, involving a number of model binary as well as complex multi-component Ti alloys, and the use of two different AM approaches, that the latter mechanism is more reliable regarding prediction of the grain morphology resulting from given solute additions.

First Report of Rust Caused by Puccinia similis on Artemisia tridentata in Idaho and Oregon.

Artemisia tridentata Nutt. (Asteraceae), commonly called sagebrush or big sagebrush, is a coarse, hardy, silvery-gray bush growing in arid sections of the Great Basin Desert of intermountain plateau covering portions of California, Idaho, Nevada, Oregon, Utah, and Wyoming in the western United States. Sagebrush is a key component of these ecosystems, providing canopy cover, nesting habitat, and a food source for numerous species of small animals and birds (4). During a plant disease survey in the Treasure Valley Region of southwestern Idaho and eastern Oregon, symptoms and signs of rust were observed on leaves of sagebrush in July 2007. Ten of fifteen plants (~70%) observed at the site were infected. Leaf samples of sagebrush with rust were also collected from a hedge in a home garden in Canyon County, ID in May 2006 and September 2007. Symptoms on both samples included cinnamon-brown, raised uredinia, primarily on the adaxial leaf surfaces. Initially, sori were scattered, increasing in density and becoming confluent. Urediniospores were thick walled, subglobose to obovoid, golden brown, echinulate, with three +/- equatorial germ pores, and measured 28 to 32 × 23 to 27 µm. Telia appeared late in the season (July to August) and were mostly scattered, becoming confluent and forming raised, ovoid, brown-to-dark red streaks on leaves and stems. Teliospores were brown to dark red, two-celled, averaging 45 × 26 µm, thick walled (average 0.75 to 1.5 µm), thickening at the apex, ellipsoid to broadly ellipsoid, with thin-walled, hyaline pedicels, 26 to 31 µm broad at attachment, tapering below, equal to or up to twice as long as the spore. On the basis of morphology, this pathogen was identified as Puccinia similis Ellis & Everh. (2), an autoecious rust previously reported from Arizona and Wyoming on A. tridentata and A. nova A. Nels. (3). To confirm the identification of the specimens from Idaho, an ~1,000 bp of DNA from the ribosomal 28S large subunit was amplified and sequenced with rust-specific primers (1) (GenBank No. GU168942). Since there are no sequences of P. similis available in GenBank for comparison, a sequence of the same gene was also obtained from a specimen of P. similis that had been collected on A. cana Pursh in Utah in 1995 by C. T. Rogerson and deposited in the U.S. National Fungus Collections (BPI 863644; GenBank No. GU168943). The sequences shared 100% identity and did not match any other species of rust in GenBank. To our knowledge, this is the first report of P. similis in Idaho and Oregon on sagebrush, and the first report, based on herbarium data, of this rust on A. cana in Utah. Voucher specimens from Idaho have been deposited in BPI (878064) and the Bernard Lowy Mycological Herbarium (LSUM). References: (1) M. C. Aime. Mycoscience 47:112, 2006. (2) G. B. Cummins. Rust Fungi on Legumes and Composites in North America. University of Arizona Press, Tucson, 1978. (3) D. F. Farr et al. Fungal Databases. Systematic Botany and Mycology Laboratory, Online publication. USDA-ARS, 8 July 2009. (4) B. L. Welch and C. Criddle, USDA Forest Service Res. Pap. RMRS-RP-40. 2003.

First Report of Powdery Mildew Caused by Leveillula taurica on Giant Blazing Star (Mentzelia laevicaulis).

Mentzelia laevicaulis (Dougl. ex Hook.) Torr. & Gray (Loasaceae; common names are giant blazing star and smoothstem blazing star) is widely distributed throughout western North America in sites ranging from lowland deserts to mountainous areas in Canada and the United States. During a plant disease survey in June 2007 in the Owyhee Mountains, Canyon County, Idaho, leaves of M. laevicaulis displaying whitish, mycelial growth were collected from plants growing on stream banks and gravelly road embankments. Diseased leaves exhibited localized, chlorotic discolorations associated with signs of a powdery mildew. Of approximately 20 plants at the site, 50% were infected. White mycelia and conidia were more abundant on the adaxial leaf surfaces than on the abaxial surfaces. Severely diseased leaves were buckled and slightly twisted. By August and through September, sporulation was greatest on mature plants, and lowermost leaves were completely covered with flocculose, dense, white mycelia. Dimorphic conidia were lanceolate or cylindrical and measured (44-) 46 to 67 (-71) × (14-) 14.5 to 20 (-21) µm. DNA was extracted and PCR was used to amplify the internal transcribed spacer (ITS) region as described previously (2), except that primers ITS 5 and P3 (4) were used. The resulting 633-bp sequence (GenBank Accession No. GQ860947) included a 616-bp region identical to a sequence reported previously for Leveillula taurica (Lév.) Arnaud from eastern Washington (GenBank No. AY912077), as well as ITS regions from L. taurica previously reported from Iran (GenBank No. AB048350) (2) and Australia (GenBank No. AF 073351) (2). Based on the ITS sequence, the present fungus grouped within Khodaparast et al. (3) Clade 1 that included L. taurica strains they distinguished from other, superficially similar species of Leveillula. On the basis of morphological and sequence data, the fungus was determined to be L. taurica (1,3). A voucher specimen was deposited in the Mycology Herbarium (WSP) at Washington State University. To our knowledge, this is the first report of a named powdery mildew species from a member of the Loasaceae. The only previous report of a powdery mildew on a loasaceous host was an undetermined Oidium sp. on a species of Mentzelia (1). The discovery of L. taurica on a previously unknown native host species is further evidence that this introduced pathogen is becoming endemic to the Pacific Northwest. Native host species, such as M. laevicaulis, may play a role in the epidemiology of powdery mildew diseases caused by L. taurica on crop and ornamental species in the Pacific Northwest. References: (1) U. Braun. Beih. Nova Hedwigia 89:1, 1987. (2) D. A. Glawe et al. Mycol. Prog. 4:291, 2005. (3) S. A. Khodaparast et al. Mycol. Res. 105:909, 2001. (4) S. Takamatsu and Y. Kano. Mycoscience 42:135, 2001.

Identification of New Alternative Weed Hosts for Iris yellow spot virus in the Pacific Northwest.

Iris yellow spot virus (IYSV; family Bunyaviridae, genus Tospovirus) is an economically important viral pathogen of onion bulb and seed crops in several parts of the United States and the world (1). IYSV is primarily transmitted by onion thrips (Thrips tabaci) and there is no evidence of seed transmission (1). However, susceptible cultivated and weed species could serve as reservoirs of inoculum from which thrips could acquire the virus to introduce and spread it in onion fields. Samples from asymptomatic and symptomatic volunteer onion plants in some of the commonly cultivated crops in the region (corn, wheat, grapes, mint, carrot, alfalfa, and sugar beets) and several common weeds in and around onion bulb and seed fields with a history of IYSV in Idaho and Washington were collected during the months of July, August, September and October of 2006. More than 175 samples from 35 plant species were analyzed for IYSV by a commercially available ELISA kit (Agdia Inc., Elkhart, IN). With the exception of a few volunteer onions, none of the other plant species had any symptoms of virus infection. Symptoms on volunteer onions included characteristic diamond-shaped lesions. To confirm the presence of IYSV in the ELISA-positive samples, total nucleic acids were extracted (2) and used in a reverse transcription (RT)-PCR assay (3). The primer pair consisted of 5'-TAA AAC AAA CAT TCA AAC AA-3' and 5'-CTC TTA AAC ACA TTT AAC AAG CAC-3'. This primer pair flanks the nucleocapsid (N) gene of IYSV and generates an approximate 1.2-kb amplicon (3) that includes the complete N gene. An amplicon of expected size was obtained from each IYSV-positive sample. The amplicons were cloned and sequenced. There was a 95% sequence identity with known IYSV sequences. While several weed species gave ELISA values that suggested the presence of IYSV, results of RT-PCR assays failed to confirm the presence of the virus. This discrepancy between ELISA and RT-PCR results could be due to nonspecific reaction in ELISA (4) or difficulty associated with obtaining RT-PCR-quality templates for amplification. Only volunteer onions and the following weeds tested positive for IYSV by ELISA and RT-PCR: redroot pigweed (Amaranthus retroflexus), puncturevine (Tribulus terrestris), kochia (Kochia scoparia), prickly lettuce (Lactuca serriola), and common lambsquarters (Chenopodium album). Of these, redroot pigweed was recently reported to be ELISA-positive for IYSV (1). This information on the wider natural host range of IYSV, including potential alternative hosts that could serve as virus reservoirs, is useful for a better understanding of the disease epidemiology and in developing an integrated management strategy for reducing the impact of this disease. References: (1) D. Gent et al. Plant Dis. 90:1468, 2006. (2) H. R. Pappu et al. HortScience 40:697, 2005. (3) H. R. Pappu et al. Arch. Virol. 151:1015, 2006. (4) T. N. Smith et al. Plant Dis. 90:729, 2006.

Powdery Mildew Caused by Leveillula taurica on Glossy Leaf Genotypes of Onion in Idaho.

Onion (Allium cepa L.) plants growing in a breeding nursery in Canyon County, Idaho were observed with leaf symptoms of powdery mildew in August and September, 1994. The affected leaves showed roughly circular, 10- to 15-mm-diameter, powdery, white-to-grayish white patches with irregular margins. The leaf area under the fungal growth turned chlorotic and later necrotic. Occasionally, lesions coalesced, covering larger areas of the leaf surface. Symptoms were seen on mature and young leaves. Of 620 lines examined, only the 10 lines which had glossy leaves (no or low levels of cuticular wax) displayed symptoms of powdery mildew. Microscopic examination revealed that the white, powdery growth on the lesions consisted entirely of conidiophores and conidia. Conidiophores emerged through stomata, singly or in groups of two or three, were branched, and bore either terminal, pyriform (59 to 68 × 16 to 19 µm), apically pointed (lanceolate) primary conidia or cylindrical (57 to 62 × 18 to 20 µm) secondary conidia. On the basis of the presence of endophytic mycelium, morphological characteristics of the conidiophores, and the dimorphic conidia the fungus was identified as Leveillula taurica (Lev.) G. Arnaud (1) (anamorph = Oidiopsis sicula Scalia). The teleomorph of this fungus was not observed. Greenhouse inoculations were made onto leaves of three 8-week-old plants of a glossy leaf onion genotype (94P240) and three 6-week-old plants of tomato (cv. Payette) grown in pots. Conidia from sporulating lesions on onion leaves were brushed onto the leaves, and the inoculated plants were covered with a plastic bag for 72 h to maintain high humidity. Inoculated leaves on both hosts developed chlorotic lesions with sporulation of L. taurica after 14 days at 25 to 28°C. Noninoculated onion and tomato plants (one of each) did not develop powdery mildew symptoms. This selective susceptibility of onion genotypes with glossy leaves to L. taurica warrants careful consideration by onion breeding programs in utilizing such germ plasm as a potential source for other desirable characters such as nonpreference to thrips. To our knowledge, this is the first report of powdery mildew of onion caused by L. taurica in Idaho. This disease has been reported on onions in California (3) and Washington (2). However, it has not been observed in commercial onion crops in Idaho, even though the cultivars involved apparently vary as to the amount of cuticular wax on their foliage. References: (1) H. J. Boesewinkel. Bot. Rev. 46:167, 1980. (2) L. J. du Toit et al. Online publication. DOI: 10.1094/PHP-2004-1129-01-HN. Plant Health Progress, 2004. (3) F. F. Laemmlen and R. M. Endo. Plant Dis. 69:451, 1985.

Aortic sinotubular junction calcium as a marker of severe aortic atherosclerosis.

Because the significance of calcification of the sinotubular junction is poorly understood, we retrospectively investigated its association with aortic atherosclerosis in 101 patients who underwent transesophageal echocardiography. Such calcification was found to be a marker of more severe aortic atherosclerosis and, specifically, aortic arch disease.

Functional significance of coronary collateral vessels in patients with previous 'Q' wave infarction: relation to aneurysm, left ventricular end diastolic pressure and ejection fraction.

The importance of coronary collateral circulation in relation to the left ventricular function, aneurysm formation and size was investigated in 100 patients with previous 'Q' wave myocardial infarction who underwent coronary angiography. Aneurysms were present in 20% of patients. The majority of these (80%) patients had severe or total occlusion of the left anterior descending artery. Thirty four percent of patients without aneurysm had significant collaterals whereas 25% of patients with aneurysms had collaterals (P > 0.05). However, the size of the aneurysm was smaller when adequate collateral circulation was present (Collateral Index 2 or above). The incidence of hypertension and diabetes was similar in both groups. Collateral circulation was more frequently seen in the anterior (60%) as compared to inferior myocardial infarction (40%), but Collateral Index was higher in right coronary artery disease. The number of patients with an elevated left ventricular end-diastolic pressure (> 12) or poor ejection fraction was similar in the two groups with and without collaterals. Thus, there was no beneficial effect of collateral circulation on left ventricular function. The incidence of aneurysm was not significantly lower, although the size of the aneurysm was significantly smaller in the presence of collateral circulation.

Powdery Mildew Caused by Erysiphe pisi on Alfalfa in Idaho and Oregon.

During July to November 2000, alfalfa (Medicago sativa L.) plants with powdery mildew symptoms were observed in commercial hay and seed fields, research plots, and a greenhouse in southwestern Idaho (Canyon County) and eastern Oregon (Malheur County). Affected leaves and stems showed white, effuse, dense, amphigenous mycelium bearing Oidium conidia, often with necrotic, brown blotches or streaks. In July, symptoms and signs were found mostly on the lower stems and leaves, but by October, all aerial parts of the plants were involved. Based on location of the mycelium and the conidiophore and conidial characteristics, the fungus was identified as Erysiphe pisi (J. C. David, personal communication). Cleistothecia were not observed. Natural incidence of the disease, which varied from less than 5% infected plants in July to more than 90% infected plants in November, was observed in commercial fields of cvs. Pioneer 53V08 (hay), Sparta (hay), and DS 907 (seed); in research (seed production) plots on cvs. Alfagraze, Anchor, Barrier, Beaver, Cut'N'Graze, Rambler, and Rangelander; and in the greenhouse on cvs. Aggressor, Archer II, Nemagone, Pecos, and Robust. Greenhouse inoculations by dusting with conidia from infected alfalfa plants (cv. Pioneer 53V08) demonstrated the susceptibility of alfalfa cvs. Affinity, Amerigraze, Innovator, and Salado and pea (Pisum sativum L.) cvs. Aladdin, Badger, Bolero, Cabree, Dwarf Gray Sugar, Early Perfection, Encore, Lazor, Maestro, Melting Sugar, Novella, Pursur, Somerwood, Spring, Stampede, and Sugar Ann. Red clover (Trifolium pratense L.) cvs. Redland, Redland II, and Premier showed positive but limited symptoms (smaller colonies, scant mycelium, and brown necrosis) following inoculation. Uninoculated control plants remained free from powdery mildew. Previous reports of powdery mildew on alfalfa in the United States (2) have attributed it to E. polygoni (Massachusetts and Wyoming) or Oidium sp. (Hawaii). Recently, powdery mildew caused by E. pisi was reported from alfalfa in research nurseries and greenhouses in Wisconsin (1). To our knowledge, this is the first report of occurrence of powdery mildew of alfalfa caused by E. pisi in the northwestern U.S., and may constitute a potential new problem for hay and seed production in this region. References: (1) J. I. Edmunds et al. Plant Dis. 82:832, 1998. (2) D. F. Farr et al. 1989. Fungi on Plants and Plant Products in the United States. APS Press, St. Paul, MN.

Bacterial Leaf Stripe Caused by Xanthomonas translucens pv. cerealis on Intermediate Wheatgrass in Idaho.

Intermediate wheatgrass (Thinopyrum intermedium [Host] Barkworth & D.R. Dewey) (synonyms: Agropyron intermedium [Host] Beauv.; Elytrigia intermedia [Host] Nevski) is widely grown as a forage crop and is also used to control soil erosion. In a seed production field of cv. Rush in Washington County, ID, more than 80% of the plants were found affected by a disease with leaf stripe symptoms. The lesions were initially elongated, water-soaked, and translucent, later developing into brown, necrotic, interveinal stripes that often coalesced. Frequently, yellowish, dried, granular, or flaky exudate was present on the lesion surfaces. Microscopic examination of cut pieces of symptomatic tissue showed profuse bacterial streaming. Isolations on nutrient agar and King's medium B agar consistently yielded smooth, circular, butyrous, yellow, raised bacterial colonies. The bacterium was rod-shaped, Gram-negative, oxidase-negative, aerobic, and did not reduce nitrate. Substrate utilization profiles (Biolog Inc.), and cellular fatty acid analysis (Analytical Services Inc.) identified the bacterium as a pathovar of Xanthomonas translucens (syn: X. campestris pv. translucens). For pathogenicity tests, 3- to 5-week-old greenhouse-grown seedlings were injected in the whorl with a water suspension of 24-h-old culture (approximately 107 cfu/ml) of the bacterium. Control plants were injected with sterile distilled water. The plants were incubated at 25 to 28°C and observations were recorded after 6 to 10 days. The bacterium was pathogenic (causing water-soaked lesions, often with bacterial exudate) to T. intermedium cvs. Rush, Tegmar, PI 547316, and PI 380636; wheat cvs. Stephens, Vandal, FF 301, and FFR 525; barley cvs. Galena, Lud, and Steptoe; oat cvs. Boone, Clinton, Erban, Marion, Mohawk, Nemaha, Olena, and Tama; rye cvs. Florida 401, Hazel, Musketeer, Oklon, Rymin, Wintermore, and Wrens 96; Agropyron cristatum cv. Ephraim; A. cristatum × desertorum cv. Hycrest; Bromus arvensis; B. briziformis; B. catharticus; B. inermisssp. inermis; B. inermis ssp. pumpellianus; B. japonicus; B. marginatus; B. popovii; B. rigidus; B. tomentellus; Dactylis glomerata cvs. Paiute and Potomac; Elymus repens; Leymus mollis; L. angustus cv. Prairieland; Lolium arundinaceum cv. Fawn; L. perenne cv. Zero Nui; and Psathyrostachys juncea cv. Bozoisky. It was only weakly pathogenic (with small, chlorotic or water-soaked lesions and no exudation) to Phleum pratense cv. Climax and Pseudoroegneria spicata ssp. spicata cv. Goldar. It was not pathogenic to Andropogon gerardii cv. Pawnee; Festuca ovina; Oryza sativa cvs. Cypress, Newbonnet, and M201; or Schizachyrium scoparium cv. Camper. Based on the pathogen's natural host and its wide host range among cereals and grasses as verified by inoculation, the bacterium was identified as X. translucens pv. cerealis. This is the first report of natural occurrence of this pathogen on T. intermedium. A sample (105 g) of seed used for planting the affected field was found contaminated with 7.5 × 104 cfu/g of the pathogen, and seed to seedling transmission was observed in greenhouse tests. Contaminated seed, thus, may serve as a source of primary inoculum to intermediate wheatgrass, which in turn may serve as an inoculum source to other susceptible cereals and grasses growing in the vicinity.

Statistical optimization of process parameters for the production of tannase by Aspergillus flavus under submerged fermentation.

Production of tannase by Aspergillus flavus (MTCC 3783) using tamarind seed powder as substrate was studied in submerged fermentation. Plackett-Burman design was applied for the screening of 12 medium nutrients. From the results, the significant nutrients were identified as tannic acid, magnesium sulfate, ferrous sulfate and ammonium sulfate. Further the optimization of process parameters was carried out using response surface methodology (RSM). RSM has been applied for designing of experiments to evaluate the interactive effects through a full 31 factorial design. The optimum conditions were tannic acid concentration, 3.22 %; fermentation period, 96 h; temperature, 35.1 °C; and pH 5.4. Higher value of the regression coefficient (R2 = 0.9638) indicates excellent evaluation of experimental data by second-order polynomial regression model. The RSM revealed that a maximum tannase production of 139.3 U/ml was obtained at the optimum conditions.

Association between socio-demographics and alcohol dependence among individuals living in an Indian setting.

BACKGROUND: Alcohol use is on the rise worldwide and urgent steps are required to curb this growing burden of alcohol consumption. Alcohol drinking leads to serious social, physical and mental consequences. OBJECTIVE: The objective of this pilot study is to examine association between socio-demographics and severity of alcohol dependence among individuals obtaining treatment at alcohol de-addiction center. METHODS: This pilot cross sectional study was conducted in September 2013 in South India. A convenient sample of 100 participants was enrolled. Individuals aged 30 years and above, receiving treatment from de-addiction center and providing written informed consent were eligible for the study. A modified version of previously validated questionnaires was used for gathering information on socio-demographic characteristics, severity of alcohol dependence (using Alcohol Dependent Scale [ADS] and Short Alcohol Dependence Data questionnaire [SADD]), motivational incentives for alcohol quitting and challenges faced while quitting alcohol. RESULTS: All participants were males with mean age of 43 years (SD = 6.5 years). Significant association was seen between ADS and annual income (p = 0.001), education (p = 0.001), occupation (p < 0.0001) and work timing (p < 0.0001). Similar results were seen with SADD scores. Family support (100%) and health (60%) were reported to be the most important motivating factors for quitting alcohol. DISCUSSION: Results showed an urgent need of interventions that are family centered and focus on unskilled, less educated individuals having high work stress. Public health interventions should not only be home based, but should also include worksite awareness initiatives. A national policy is needed to promote alcohol quitting and to bring awareness regarding the consequences of alcohol consumption on individual's life.

Sequence diversity of the nucleoprotein gene of iris yellow spot virus (genus Tospovirus, family Bunyaviridae) isolates from the western region of the United States.

Iris yellow spot virus (IYSV), a tentative virus species in the genus Tospovirus and family Bunyaviridae, is considered a rapidly emerging threat to onion production in the western United States (US). The present study was undertaken to determine the sequence diversity of IYSV isolates from infected onion plants grown in California, Colorado, Idaho, Oregon, Utah and Washington. Using primers derived from the small RNA of IYSV, the complete sequence of the nucleoprotein (NP) gene of each isolate was determined and the sequences compared. In addition, a shallot isolate of IYSV from Washington was included in the study. The US isolates of IYSV shared a high degree of sequence identity (95 to 99%) with one another and to previously reported isolates. Phylogenetic analyses showed that with the exception of one isolate from central Oregon and one isolate from California, all the onion and shallot isolates from the western US clustered together. This cluster also included onion and lisianthus isolates from Japan. A second distinct cluster consisted of isolates from Australia (onion), Brazil (onion), Israel (lisianthus), Japan (alstroemeria), The Netherlands (iris) and Slovenia (leek). The IYSV isolates evaluated in this study appear to represent two distinct groups, one of which largely represents isolates from the western US. Understanding of the population structure of IYSV would potentially provide insights into the molecular epidemiology of this virus.