PROGRAM AND NONPROGRAM WHEAT ACREAGE RESPONSES TO PRICES AND RISK

Wheat acreage responses to expected wheat price and price risk are reversed for program and nonprogram-planted acreage in the northern plains, central plains, southern plains, and U.S. Expected wheat price has a strong negative effect on program-complying wheat acreage. Government support prices have a positive effect on program-complying and program-planted acreage. Price risk has a positive effect on program-complying wheat acreage and a negative effect on nonprogram-planted acreage. Estimated price elasticities are higher than in studies where risk was ignored.Demand and Price Analysis, Risk and Uncertainty,

Mehanizam akutne neurotoksičnosti u Sprague-Dawley štakora izazvane trovanjem endosulfanom

The purpose of this study was to investigate the molecular mechanism underlying oxidative and inflammatory neuronal cell death induced by endosulfan, a pesticide belonging to the chemical family of organochlorines. The cortical and hippocampal tissues derived from Sprague-Dawley (SD) rats treated with endosulfan exhibited increased intracellular accumulation of reactive oxygen species and oxidative damages to cellular macromolecules such as depletion of glutathione, lipid peroxidation, and protein carbonylation. Conversely, the expression of antioxidant enzymes including γ-glutamylcysteine ligase (GCL), superoxide dismutase (SOD), and heme oxygenase-1 (HO-1) was markedly reduced in the brain tissues exposed to endosulfan. Moreover, during endosulfan-induced neuronal cell death, mRNA expression of pro-inflammatory cytokines such as tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) was elevated, which seemed to be mediated by the activation of nuclear factor-kappa B (NF-κB) by phosphorylation of p65 subunit. These results suggest a new molecular mechanism underlying the endosulfan-induced acute neurotoxicity via induction of oxidative stress and pro-inflammatory responses.Istražen je molekularni mehanizam koji dovodi do smrti neurona potaknute oksidativnim i upalnim procesima uzrokovanim organoklornim pesticidom endosulfanom. U tkivima korteksa i hipokampusa Sprague-Dawley (SD) štakora tretiranih endosulfanom uočena su oksidativna oštećenja staničnih makromolekula, poput smanjene razine glutationa, lipidne peroksidacije i karbonilacije proteina, te povećane unutarstanične akumulacije reaktivnih kisikovih spojeva. Isto tako, u moždanom tkivu nakon izlaganja endosulfanu značajno je smanjena ekspresija enzimskih antioksidansa, uključujući i γ-glutamilcistein ligazu (GCL), superoksidnu dismutazu (SOD) i hem oksigenazu-1 (HO-1). Tijekom endosulfanom izazvane smrti neurona povećala se i ekspresija mRNA pro-upalnih citokina poput čimbenika nekroze tumora-α (TNF-α) i interleukina-1β (IL-1β), što je čini se bilo posredovano aktivacijom nuklearnoga faktora kapa B (NF-κB) putem fosforilacije podjedinice p65. Navedeni rezultati upućuju na novi molekularni mehanizam koji stoji iza akutne neurotoksičnosti izazvane endosulfanom putem indukcije oksidativnoga stresa i pro-upalnih odgovora

Two-Dimensional Dirac Fermions Protected by Space-Time Inversion Symmetry in Black Phosphorus

We report the realization of novel symmetry-protected Dirac fermions in a surface-doped two-dimensional (2D) semiconductor, black phosphorus. The widely tunable band gap of black phosphorus by the surface Stark effect is employed to achieve a surprisingly large band inversion up to ~0.6 eV. High-resolution angle-resolved photoemission spectra directly reveal the pair creation of Dirac points and their moving along the axis of the glide-mirror symmetry. Unlike graphene, the Dirac point of black phosphorus is stable, as protected by spacetime inversion symmetry, even in the presence of spin-orbit coupling. Our results establish black phosphorus in the inverted regime as a simple model system of 2D symmetry-protected (topological) Dirac semimetals, offering an unprecedented opportunity for the discovery of 2D Weyl semimetals

A Three-Dimensional Micro-Organ Culture System for Microtumor Spheroids from Human Malignant Glioma Specimens

Tumor.tissue obtained from seven human malignant gliomas was minced and explanted into agarose-coated culture plates. After five to seven days, these microtumor fragments emerged as spheroids in four tumors and were maintained as multicellular organotypic spheroids for more than eight weeks. The morphological features and growth characteristics of different spheroids were studied and compared with the histology of the original tumor specimens. Light microscopic and ultrastructural studies of the spheroids demonstrated that morphological structures were similar to those of the original tumor tissue in vivo. The microtumor spheroids contained connective tissue, blood vessels, and macrophages, maintaining a three dimensional-architectural resemblance to the original tumors. Volumetric measurement of the spheroids showed that the size decreased initially and did not change thereafter over a period of time. This growth pattern of the spheroids was consistent with that of tumors in vivo, suggesting the linkage of cell proliferation and loss. This in vitro culture system for surgically removed brain tumor specimens may serve as an alternative to the in vivo xenograft model for the research of brain tumor biology, invasion and immunology and provide a valuable technique for the evaluation of new therapies, such as biologic response modifiers

The impact of sequential versus single anastomoses on flow characteristics and mid-term patency of saphenous vein grafts in coronary bypass grafting

ObjectiveTo assess the influence of bypass grafting technique on the flow characteristics and mid-term patency of saphenous vein coronary bypass grafts.MethodsIn the present study, 309 patients who underwent either sequential (group A, N = 84 grafts) or individual (group B, N = 244 grafts) saphenous vein coronary bypass grafting between February 2002 and September 2007 were investigated. Individual bypassing only was performed in 212 patients, and sequential bypassing only was performed in 78 patients. The remaining 19 patients received both. A total of 436 distal anastomoses were performed with 328 saphenous vein grafts. The intraoperative flow characteristics and the graft patency were assessed with the transit time flow meter and serial multi-detector computed tomography coronary angiograms, respectively.ResultsGroup A showed a higher mean flow compared with group B at 49.4 ± 27.4 mL/min versus 37.1 ± 20.1 mL/min, respectively (P = .001). The mean flow increased linearly as the number of anastomoses increased per graft (P < .001). Graft patency at 3 years was 93.3% ± 3.4% in group A and 86.5% ± 3.1% in group B (P = .048). After adjustment for baseline characteristics, group A showed a tendency for superior mid-term patency than group B (hazard ratio 0.362; 95% confidence interval, 0.129–1.017; P = .0538).ConclusionsSequential bypass grafts were associated with higher mean flows and superior mid-term patency compared with individual grafts. These findings suggest the more favorable results of sequential bypass grafting to be attributed to the enhanced flow hemodynamics

Digital Workflow for Retrofitting a Surveyed Crown Using a Removable Partial Denture as an Antagonist

Digital workflow expedites the procedure of retrofitting a surveyed crown against an existing removable partial denture (RPD). This article describes a simple and straightforward technique of digital workflow where an existing RPD is scanned as an antagonist to design the rest seat, guide plane, and height of contour of a surveyed crown.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156192/2/jopr13187_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156192/1/jopr13187.pd