A convergent synthetic route to the tunicamycin antibiotics. Synthesis of (+)-tunicamycin V

The tunicamycins are a family of natural products represented generally by structure 1, wherein R indicates one of several long-chain branched, linear, saturated or unsaturated acyl substituents. They elicit a considerable range of biological responses including antimicrobial, antifungal, antiviral, and antitumor activities. Their ability to function as potent inhibitors of oligosaccharide synthesis in eukaryotic cells has established them as unique biochemical probes of the role of glycosylation on protein structure and function. In this work, we describe a concise synthetic route to the tunicamycins, illustrated by the preparation of (+)-tunicamycin V (1-V)

MF2242

Daniel O'Brien et al., Economic comparison of SDI and center pivots for various field sizes, Kansas State University, October 1997

Robotic partial nephrectomy for posterior tumors through a retroperitoneal approach offers decreased length of stay compared with the transperitoneal approach: A propensity-matched analysis

INTRODUCTION: We sought to compare surgical outcomes between transperitoneal and retroperitoneal robotic partial nephrectomy (RPN) for posterior tumors. PATIENTS AND METHODS: Using our multi-institutional RPN database, we reviewed 610 consecutive cases for posterior renal masses treated between 2007 and 2015. Primary outcomes were complications, operative time, length of stay (LOS), surgical margin status, and estimated glomerular filtration rate (eGFR) preservation. Secondary outcomes were estimated blood loss, warm ischemia time (WIT), disease recurrence, and disease-specific mortality. Due to significant differences in treatment year and tumor size between approaches, retroperitoneal cases were matched 1:4 to transperitoneal cases based on propensity scores using the greedy algorithm. Outcomes were compared between approaches using the chi-square and Mann-Whitney U tests. RESULTS: After matching, 296 transperitoneal and 74 retroperitoneal cases were available for analysis, and matched groups were well balanced in terms of treatment year, age, gender, race, American Society of Anesthesiologists physical status classification (ASA) score, body mass index, tumor laterality, tumor size, R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to the collecting system or sinus, anterior/posterior, location relative to polar lines) score, and hilar location. Compared with transperitoneal, the retroperitoneal approach was associated with significantly shorter mean LOS (2.2 vs 2.6 days, p = 0.01), but longer mean WIT (21 vs 19 minutes, p = 0.01). Intraoperative (p = 0.35) and postoperative complications (p = 0.65), operative time (p = 0.93), positive margins (p = 1.0), and latest eGFR preservation (p = 0.25) were not significantly different between approaches. No differences were detected in the other outcomes. CONCLUSIONS: Among high-volume surgeons, transperitoneal and retroperitoneal RPN achieved similar outcomes for posterior renal masses, although with slight differences in LOS and WIT. Retroperitoneal RPN may be an effective option for the treatment of certain small posterior renal masses

Coastal Change and Beach Ridges along the Northwest Coast of Peru: Image and GIS Analysisof the Chira, Piura, and Colán Beach-Ridge Plains

Since approximately 5200 cal yrs BP, five sets of eight to nine beach ridges were built and preserved along the northwestern Peruvian coastal desert (3o30\u27S-9oS). Potential ridge-building mechanisms in the hyper-arid environment of northwest Peru include El Nifio floods and storms, seismic activity, and sea-level change, as well as more gradualc limate changes that affectedc oastal morphologyI. mage processinga nd GeographicI nformationS ystem (GIS) methods were used to analyze aerial photographs and measure historic coastal patterns along three beach-ridge plains over a 37-year time period. Coastal features were digitized from image mosaics of each ridge plain at different time intervals from 1946 up to 1983. Progradation rates were examined at ridge locations north of the Chira River and Piura River, as well as at the base of ephemeral stream valleys in Colin. The total change in beach area was measured from historic aerial photographs taken at different time intervals. The resulting measurements showed that sediment distributed by El Nifio storms was redeposited along the shoreline within a few years following each event. The difference between the frequency of El Nifio events (currently 2-7 years) and the rate of ridge preservation (1 per 500 years average) suggests that individual ridges may be composites of multiple depositional events, or that ridges result from the rare convergence of multiple processes and conditions. A change in style of ridge formation in all studied beach-ridge sets correlates with, and may be explained by, change in the frequency of El Nifio events at about 3000 cal yrs BP

MF2471

Daniel M. O'Brien, et al, The economics of converting from surface to sprinkler irrigation for various pumping capacities, Kansas State University, November 2000

Proceedings of the 24th annual Central Plains irrigation conference

Presented at Proceedings of the 24th annual Central Plains irrigation conference held on February 21-22 in Colby, Kansas.Includes bibliographical references

Using the K-State center pivot sprinkler and SDI economic comparison spreadsheet - 2008

Presented at the 2008 Central Plains irrigation conference on February 19-20 in Greeley, Colorado.Includes bibliographical references

The Determinants of Student Performance in Indonesian Public Primary Schools: the Role of Teachers and Schools

In this paper we investigate the determinants of student performance in mathematics and dictation tests among fourth-grade school children in Indonesia. we use a unique dataset of school and student information that was collected in a nationally representative survey of 110 public schools in 8 Indonesian provinces in 2003. using an ols regression technique that compensates for heteroskedasticity, we conduct separate sets of student-level regressions for three performance variables: math scores, dictation scores and combined scores. we found that student performance is strongly influenced by individual variables, teacher variables and school variables. among the significant variables are the education level of parents; student-teacher ratio; quality of school facilities and teacher absence rate. we also discuss the policy implications of the results. key words: absenteeism; primary school; achievement

Proceedings of the 23rd annual Central Plains irrigation conference

Presented at Proceedings of the 23rd annual Central Plains irrigation conference held in Burlington, Colorado on February 22-23, 2011.Includes bibliographical references