Gas to protein: Microbial single cell protein is an alternative to fishmeal in aquaculture.

Methanotrophic bacteria represent an appealing opportunity to convert methane, a potent greenhouse gas, into a highly nutritious animal feed ingredient, single-cell protein (SCP). SCP has a comparable or superior nutritional profile that to most conventional protein sources and can be produced within a lower environmental footprint. The present study investigated the effect of replacing fishmeal (FM) with methanotrophic SCP in diets for barramundi (Lates calcarifer), a carnivorous fish with a high demand for dietary protein and energy. Dietary inclusion levels of 0 %, 10 %, 20 % and 30 % SCP (representing 0, 25, 50 and 75 % FM replacement) were tested, with and without additives. Triplicate groups of juvenile barramundi were fed the diets over 31 days. The inclusion of SCP significantly improved weight gain and feed conversion efficiency (FCE). Dietary SCP inclusion supported good gut health, with decreasing trends of hepatosomatic index, improved plasma biochemistry, and no adverse histopathological changes. Barramundi fed the SCP diets showed an intact intestinal barrier and a significant improvement in villi and lamina propria area when fed the additive supplemented SCP diets. This study demonstrates that this SCP is highly palatable to barramundi (even without dietary additives) and can replace up to 75 % FM with significant improvements in growth and FCE.

Adequate levels of dietary sulphur amino acids impart improved liver and gut health in juvenile yellowtail kingfish (Seriola lalandi).

The sulphur amino acids methionine (Met) and cysteine (Cys) and their derivative taurine (Tau) are metabolically active molecules with interlinked roles in nutritional requirements. Deficiencies in these nutrients are linked to poor growth and health; however, the impacts of these deficiencies on organ structure and function are largely unknown. This study examined the effects of dietary Met, Cys and Tau fed at different levels on yellowtail kingfish (YTK) liver histology and surface colour, plasma biochemistry and posterior intestine histology. Samples were collected from two dose-response feeding trials that quantified (1) the Tau requirement and sparing effect of Met by feeding YTK diets containing one of seven levels of Tau at one of two levels of Met and (2) the Met requirement and sparing effect of Cys by feeding YTK diets containing one of five levels of Met at one of two levels of Cys. YTK fed inadequate levels of dietary Met, Cys and Tau exhibited thicker bile ducts, less red livers, more intestinal acidic goblet cell mucus and supranuclear vacuoles and less posterior intestinal absorptive surface area. Further, thicker bile ducts correlated with less red livers (a*, R), whereas increased hepatic fat correlated with a liver yellowing (b*). Our results indicate a shift towards histological properties and functions indicative of improved intrahepatic biliary condition, posterior intestinal nutrient absorption and homoeostasis of YTK fed adequate amounts of Met, Cys and Tau. These findings may assist in formulating aquafeed for optimised gastrointestinal and liver functions and maintaining good health in YTK.

Effects of dietary choline on liver lipid composition, liver histology and plasma biochemistry of juvenile yellowtail kingfish (Seriola lalandi).

Choline plays a crucial role in lipid metabolism for fish, and its deficiency in aquafeed has been linked to compromised health and growth performance. A 56-d experiment was conducted to examine the effects of dietary choline on lipid composition, histology and plasma biochemistry of yellowtail kingfish (Seriola lalandi; YTK; 156 g initial body weight). The dietary choline content ranged from 0·59 to 6·22 g/kg diet. 2-Amino-2-methyl-1-propanol (AMP) (3 g/kg) was added to diets, except for a control diet, to limit de novo choline synthesis. The results showed that the liver lipid content of YTK was similar among diets containing AMP and dominated by NEFA. In contrast, fish fed the control diet had significantly elevated liver TAG. Generally, the SFA, MUFA and PUFA content of liver lipid in fish fed diets containing AMP was not influenced by choline content. The SFA and MUFA content of liver lipid in fish fed the control diet was similar to other diets except for a decrease in PUFA. The linear relationship between lipid digestibility and plasma cholesterol was significant, otherwise most parameters were unaffected. When AMP is present, higher dietary choline reduced the severity of some hepatic lesions. The present study demonstrated that choline deficiency affects some plasma and liver histology parameters in juvenile YTK which might be useful fish health indicators. Importantly, the present study elucidated potential reasons for lower growth in choline-deficient YTK and increased the knowledge on choline metabolism in the fish.

Transition metal catalysed dehydrogenation of amine-borane fuel blends.

Mixtures containing ammonia-borane and sec-butylamine-borane remain liquid throughout the hydrogen release process that affords tri(N-sec-butyl)borazine and polyborazylene. Concentrated solutions with metal catalysts afford >5 wt% H(2) in 1 h at 80 °C and addition of (EMIM)EtSO(4) ionic liquid co-solvent eliminates competing formation of insoluble linear poly(aminoborane) (EMIM = 1-ethyl-3-methyl-imidazolium).

A prospective study of the longitudinal effects of an embedded specialty curriculum on physical examination skills using an ophthalmology model.

PURPOSE: To prospectively evaluate effects of a longitudinal specialty curriculum on acquisition and retention of ophthalmic screening examination skills in a single class across three years of medical school (2004-2007). METHOD: Immediately after initial Year 2 skills training, preceptors evaluated students' (N=84) acquisition of basic eye screening examination skills. Similarly, the students self-assessed their skills. In Year 3, a required ophthalmology small-group module during the family medicine (FM) clerkship reinforced these skills. The authors audited history and physicals in two Year 3 clerkships and in one Year 4 subinternship to evaluate charted examination performance. They objectively assessed simulator-based ophthalmoscopy post-FM clerkship and post-Year 3 training. RESULTS: Preceptors rated 100% of students competent in all eye examination modalities post initial training; 98% of students self-rated themselves competent in disc visualization. An expert auditor found documented FM funduscopies (46%) surpassed those in a prior observational study (11%). Funduscopic retraining significantly improved performance on post-Year 3 objective assessment (mean score 55% retrained versus 19% nonretrained, P=.0005). However, 43% of FM and 91% of internal medicine workups reflected inadequate overall eye evaluations. Subinternship notes documented muscle excursions in 95% and pupils in 71% but recorded no funduscopies. CONCLUSIONS: Additional training successfully reinforced skills performance, which nonetheless decayed when not habitually practiced. Neither physical diagnosis preceptor ratings nor excellent performance in the FM ophthalmology module predicted subsequent skills performance in other clerkships or on simulator testing. The present study supports a reiterative retraining model for teaching this and other specialty physical examination skills.

Interpreting values conflicts experienced by obstetrics-gynecology clerkship students using reflective writing.

PURPOSE: To examine students' responses to reflective practice assignments used in medical ethics and professionalism education. The study goals include an examination of what reflective writing reveals about students' personal and professional values, identification of the narrative typologies students use to tell stories of ethical dilemmas, and a determination of the usefulness of reflective writing in informing ethics/professionalism curricula assessment and development. METHOD: This study employed a mixed-methods design generating both descriptive data and interpretive analysis. Students' reflective writing assignments, guided by a series of six questions designed to elicit students' perceptions of moral conflicts they have encountered and their personal and professional ethical values, were collected from three successive cohorts of third-year medical students (n = 299) from July 2002 to January 2006 during an obstetrics-gynecology clerkship at the University of California, Irvine, School of Medicine. Content, thematic, and global narrative analyses of students' reflective writing were conducted, drawing on content analysis, grounded theory, and narrative methodologies. RESULTS: Values conflicts usually were patient centered (181; 60.5%) and student centered (172; 57.5%), without much regard for important contextual issues such as patients' socioeconomic status, insurance coverage, or culture. Common personal values included religious beliefs (82; 27.4%), respect (72; 24.1%), and the Golden Rule (66; 22.1%); frequent professional values were respect (72; 25.1%), beneficence (71; 23.7%), nonmaleficence (69; 23.1%), and autonomy (65; 21.7%). Whereas 35.5% (106) claimed to have addressed conflicts, 23.4% (70) said they did nothing. Restitution narratives (113; 37.8%) dominated. CONCLUSIONS: This analytic approach facilitated assessment of student values, conflict sources, and narrative types. Findings reveal aspects of the influence of the hidden curriculum and can inform strategies for effective implementation of bioethics/professionalism curricula.

Addressing health care needs of the Latino community: one medical school's approach.

The Program in Medical Education for the Latino Community (PRIME-LC) at the University of California-Irvine (UCI) School of Medicine was designed to improve health care delivery, research, and policy in underserved Latino communities. Specialized training develops strongly committed physicians with linguistic skills and cultural understanding, enabling them to serve Latino patients. Presently, the health care system's shortage of providers with this expertise renders it unable to address the Latino community's needs adequately. The UCI School of Medicine realized they were proposing a radically different type of program at the onset of this project -- one designed to address the health care needs of a specific ethnic group. Developed with dual goals, PRIME-LC aspires to provide the Latino community with culturally sensitive, Spanish-speaking physicians who are well aware of medical and social conditions prevalent among Latinos, in addition to physicians with a broad understanding of community medicine who are well versed in advocacy and able to become leaders within and outside the Latino community. PRIME-LC must be placed within the context of predicted physician shortages in the United States attributable to the projected population increase in general and, more specifically, within the context of a growing Latino population nationwide. As medical schools prepare to increase their output, programs like PRIME-LC that address society's special needs deserve serious consideration.

Ammonia-borane: the hydrogen source par excellence?

Ammonia-borane, H3NBH3, is an intriguing molecule for chemical hydrogen storage applications. With both protic N-H and hydridic B-H bonds, three H atoms per main group element, and a low molecular weight, H3NBH3 has the potential to meet the stringent gravimetric and volumetric hydrogen storage capacity targets needed for transportation applications. Furthermore, devising an energy-efficient chemical process to regenerate H3NBH3 from dehydrogenated BNHx material is an important step towards realization of a sustainable transportation fuel. In this perspective we discuss current progress in catalysis research to control the rate and extent of hydrogen release and preliminary efforts at regeneration of H3NBH3.

A study of the physician workforce supply for the latino population in California.

PURPOSE: To determine the physician supply during two decades to the workforce available to California Latinos from two separate training tracks at the University of California, Irvine School of Medicine (UCI)--the Fifth Pathway Program (FPP) and the traditional medical school curriculum. METHOD: In 2002, the authors compared two groups of physicians practicing in California to ascertain the percentage of Latino patients in their practices. One group had completed the FPP (n = 229) during the period 1971-1991, and UCI graduates from the same period composed the second group (n = 960). The authors also examined Latino population statistics for California communities where physicians located their practices. RESULTS: Both groups practiced in California (71.5%) and in primary care (59.9%) at the same rates. Women were underrepresented among FPP physicians (12.2% versus 33.3%). FPP physicians self-reported seeing significantly more Latino patients (14.3% versus 9.2%; P < .001). However, the groups did not significantly differ in the rates at which they practiced in communities with 40% or more Latino residents (18.1% versus 12.9%). CONCLUSIONS: Reactivating the FPP may increase the raw number of physicians in California, but two decades of this program did not recruit physicians to practice in California's Latino community at a rate much above that for traditional medical school graduates, especially for communities having the highest Latino population densities.

Mechanism of white phosphorus activation by three-coordinate molybdenum(III) complexes: a thermochemical, kinetic, and quantum chemical investigation.

White phosphorus (P(4)) reacts with three-coordinate molybdenum(III) trisamides or molybdaziridine hydride complexes to produce either bridging or terminal phosphide (P(3)(-)) species, depending upon the ancillary ligand steric demands. Thermochemical measurements have been made that place the MoP triple bond dissociation enthalpy at 92.2 kcal.mol(-)(1). Thermochemical measurements together with computational analysis rule out simple P-atom abstraction from P(4) as a step in the phosphorus activation mechanism. Kinetic measurements made by the stopped-flow method show that the reaction between the monomeric molybdenum complexes and P(4) is first-order both in metal complex and in P(4). Cyclo-P(3) complexes can be obtained when ancillary ligand steric demands are small, but kinetic measurements rule them out as monometallic intermediates in the P(4) activation mechanism. Also studied by calorimetric, kinetic, and in one case variable-temperature NMR methods is the process of mu-phosphide bridge formation. Post-rate-determining steps of the P(4) activation process were examined in a search for minima on the reaction's potential energy surface, leading to the proposal of two plausible, parallel, bimetallic reaction channels.

Molybdenum-phosphorus triple bond stabilization by ancillary alkoxide ligation: synthesis and structure of a terminal phosphide tris-1-methylcyclohexanoxide complex.

Using alcoholysis, we converted terminal phosphide PMo(N[i-Pr]Ar)3 into a new, monomeric terminal phosphide PMo(OR)3, where R = 1-methylcyclohexyl or 1-adamantyl. Dimerization of the PMo unit was observed upon alcoholysis with 2,6-dimethylphenol, and the dimer [PMo(N[i-Pr]Ar)(O-2,6-C6H3Me2)2]2 was isolated and characterized by X-ray crystallography.