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Summary paragraphVacuolar-type adenosine triphosphatases (V-ATPases)1–3 are electrogenic rotary mechanoenzymes structurally related to F-type ATP synthases4,5. They hydrolyze ATP to establish electrochemical proton gradients for a plethora of cellular processes1,3. In neurons, the loading of all neurotransmitters into synaptic vesicles is energized by ~1 V-ATPase molecule per synaptic vesicle6,7. To shed light into this bona fide single-molecule biological process, we investigated electrogenic proton pumping by single mammalian-brain V-ATPases, using individual synaptic vesicles fused with immobilized liposomes. We show V-ATPases do not pump continuously in time, as hypothesized by observing the rotation of bacterial homologs8 and assuming strict ATP/proton coupling. Instead, they stochastically switch between three novel ultra-long-lived proton-pumping, inactive, and proton-leaky modes. Upending conventional wisdom, direct observation of pumping revealed that physiologically relevant concentrations of ATP do not regulate the intrinsic pumping rate. Instead, ATP regulates V-ATPase activity via the switching probability of the proton-pumping mode. In contrast, electrochemical proton gradients regulate the pumping rate and the switching of the pumping and inactive modes. This work reveals and emphasises the mechanistic and biological importance of mode-switching in protein regulation.

Investigations relating to in-drift disposal of heat-generating nuclear waste in salt have raised questions about heat–brine interactions in the unsaturated run-of-mine (RoM) salt pile used as backfill. These interactions have the potential to change the structure of the RoM salt surrounding the canister, possibly altering long-term containment of the source. An experiment is in progress at the Waste Isolation Pilot Plant (WIPP), New Mexico, in which a heated canister was placed on the floor of an open drift, covered in a pile of RoM salt, and energized with 1000 W. Temperature in the RoM salt pile had stabilized after about 15 d, allowing evaluation of the heat-up period of the ongoing experiment. Using a multiphase porous flow simulator that has been modified to handle salt-specific coupled processes, we examined coupled thermal–hydrological–chemical behavior in the RoM salt pile. Our simulations suggest that for the relatively dry cases examined, porosity changes within RoM salt in a generic salt repository are likely to be minor in the period between waste emplacement and plastic closure of the drift. The primary sensitivity for porosity change is to the early moisture content of the RoM salt used to cover the canister. Secondary influences include moisture availability from the disturbed rock zone (DRZ) surrounding the drift and the capillary pressure ratio between the DRZ and the RoM salt. Early changes in porosity and permeability may be affected by moisture content, but this was not observed in the test. Such changes would be most likely to occur when using damp RoM salt or if waste is emplaced in a drift immediately following opening of the drift before evaporative dewatering of the drift walls occurs.

Monogenetic volcanic eruptions are generally assumed to last to tens of years and produce frequent, intermittent explosive activity that creates eruption columns up to ~ 10 km in elevation. Although this view fits the historically observed eruptions, few data have been collected about the range of durations and eruption sizes possible from monogenetic events. Examining other eruption deposits can help clarify the range of eruption styles and sizes possible from future explosive monogenetic eruptions. The ~ 38 ka Marcath event at Lunar Crater Volcanic Field, Nevada, produced a scoria cone, two tephra fall deposits, and a lava field. We reconstruct the activity that produced the largest tephra fall deposit. Explosive activity produced an eruption column up to ~ 7 km and a volume of about 0.018 km 3 . The Marcath tephra-forming activity was small compared to other characterized scoria cones. Post-eruptive remobilization of the deposit has occurred especially around the margins through both fluvial and eolian processes and has likely removed at least 0.001 km 3 of fine material from the distal portions of the deposit.

A growing number of national and international buyers are now specifying "certified" forest products in their procurement policies. In response, the Canadian Standards Association (CSA) has worked with a diverse range of stakeholders interested in Sustainable Forest Management in Canada to develop CSA's Sustainable Forest Management (SFM) Program. CSA's SFM Program consists of four distinct, yet inter-related components: CAN/CSA Z809, Canada's National Standard for Sustainable Forest Management; chain of custody for forest products; product marking with CSA International's SFM Mark; and, CSA International's Forest Products Group. When these components are combined they provide a comprehensive, credible, and affordable forest certification and product-marking program. The list of organizations accepting forest products certified through the CSA SFM Program is growing within Canada, the United States and abroad. Key words: Canadian Standards Association (CSA), forest certification, certified forest products, chain of custody, product marking, criteria and indicators.

Participation in acts of torture, despite the approval of a government agency, places physicians in a morally compromised position. Virtual Mentor is a monthly bioethics journal published by the American Medical Association.

[1] Craters at many volcanoes, including most maars, are formed by multiple subsurface explosions. Experiments compared the crater formed by a single large, buried explosion, with craters formed by multiple explosions with the same cumulative energy. Explosive charges were detonated in pads composed of layered aggregates, in three configurations: (1) a single large charge buried near its optimal crater excavation depth; (2) three charges, each with 1/3 the energy of the first one, buried at approximately the same depth with respect to the original pad surface; (3) the same three charges buried successively deeper. Final crater size in the multiple explosion cases is not a good indicator of the energy of individual explosions. However, crater morphology, and ejecta volume and distribution can be good indicators of explosion energy and depth. These results directly impact the estimate of the energy released by past maar eruptions and future hazard assessments.

LEARNREPRO consists of three computer software packages that were developed to improve dairy reproductive problem-solving skills by college students, professionals, and farmers. Tutorial, drill and practice, and simulation approaches are utilized. The module REPRO-MEASURES covers six common DHI measures of herd reproductive performance. The USE-OF-RECORDS module integrates information from the previous module while presenting additional problem-solving strategies needed to analyze DHI reproductive records. The ESTRUS-DETECTION module addresses effective estrus detection strategies. User surveys have demonstrated the need for more use of this instructional approach. Educators are encouraged to use these modules and also to develop additional computer teaching programs to facilitate the development of problem-solving skills.

Creative teaching methods aimed to train learners to improve farm management decisions need to be explored. In that context a microcomputer software package (ESTRUS-DETECTION) was developed to address a major economic problem in dairy herd management - estrus detection - by integrating tutorial and simulation instruction. ESTRUS-DETECTION was developed in the cT programming language. A pretest/posttest experimental design measured changes in learning for 45 students in an undergraduate dairy management course. Total learning was significantly increased among students. Comparable learning increases were shown for students working in pairs and individually. Student feedback and a subjective evaluation of knowledge retention affirmed the importance of integrated simulation and tutorial computer instruction as an agricultural teaching tool.

(...) An optimal internal parasite control program model is developed. The model has special relevance for developing nations with severely limited resources. A hypothetical case for sheep (Ovis aries) is used to illustrate methodology and necessary data to specify the model for any control program. Optimal solutions for several scenarios are generated to illustrate the kind of information that decision makers can obtain from goal programming

The sequel to The Rockefeller Century surveys the family's story from 1952 to the present, revealing the public uses of the vast Rockefeller wealth, as well as the private dramas that have shaped such use. Authors Harr and Johnson are the only historians who have had access to previously secret family archival materials. Photographs and index.

There has been a dramatic expansion in community-based services for mentally disabled persons, frequently giving rise to the dilemma of who can or should operate the new programs. Existing mental health provider agencies may not have the capacity or interest to mount new initiatives. Other community service organizations may not have the needed experience in mental health services. This article describes the development of a new not-forprofit corporation, using structured consultation, to initiate the needed services. This innovative strategy may have utility in other areas.

Community mental health centers are increasingly conducting studies of program effectiveness and impact. But conducting evaluative studies does not mean that the results are used in making programmatic decisions. In this study of forty-two community mental health centers, evaluative data were utilized in making some programmatic decisions, but, by far, the most important decision-making factor identified by CMHC directors was availability of funds. Few characteristics of CMHCs or their directors were associated with the use of evaluative information in programmatic decision making.

In recommendations for community support systems, there are expectations of public involvement in unprecedented proportions; yet evidence of fundamental shifts in attitudes and behaviors toward the mentally ill is lacking. Considerations of the complexity of public acceptance led to the development of a scale used to measure the extent of support for the chronically mentally ill among 574 randomly selected adults in Leon County, Florida. Comparison of the general population with residents in a neighborhood known to be opposed to community-based services served to establish the validity of the scale. The findings led to recommendations for future research in this area.

This survey assesses the practice interests and aspirations of 257 entering direct practice students in 8 MSW programs. Its findings suggest that the majority of these students seek the MSW degree as a route to becoming psychotherapists in private practice and that they have little commitment to social work’s mission, dual focus, or distinctive functions and clientele. The implications of these findings are explored.

This article examines how community mental health practitioners are likely to implement services for improving community-based care of the chronically mentally disabled. A scale is described for use by administrators to assess practitioner orientations and thereby anticipate compliance problems. Research findings comparing scale scores of state hospital and community-based practitioners are reported, indicating potential problems. Suggestions are made to help administrators alleviate these problems.

A previously reported baseline study found that most entering direct practice students aspire to become psychotherapists in private practice and have little interest in social work's distinctive person-in-environment focus, its functions, or its clientele. The current study assesses how those interests and aspirations change from entry to graduation. The findings show some decline in the appeal of psychotherapy, private practice, and most categories of clientele and case situations. Movement toward a more balanced person-in-environment perspective appears to be modest. Alternative interpretations and implications of the findings are explored.

Approximately 1400 acres are now under quarantine for the Asiatic beetle, Anomala orientalis Waterhouse, in New Haven, Conn. Altogether 2402 beetles were found during the summer scouting season, and 4576 diggings were made in the spring and fall. The heavy infestation is concentrated in 300 acres, and the larvae injure the lawns severely. Carbon disulphide emulsion was used successfully in controlling them, and during the past year 100 acres were treated.

Vacuolar-type adenosine triphosphatases (V-ATPases) are electrogenic rotary mechanoenzymes structurally related to F-type ATP synthases. They hydrolyse ATP to establish electrochemical proton gradients for a plethora of cellular processes. In neurons, the loading of all neurotransmitters into synaptic vesicles is energized by about one V-ATPase molecule per synaptic vesicle. To shed light on this bona fide single-molecule biological process, we investigated electrogenic proton-pumping by single mammalian-brain V-ATPases in single synaptic vesicles. Here we show that V-ATPases do not pump continuously in time, as suggested by observing the rotation of bacterial homologues and assuming strict ATP–proton coupling. Instead, they stochastically switch between three ultralong-lived modes: proton-pumping, inactive and proton-leaky. Notably, direct observation of pumping revealed that physiologically relevant concentrations of ATP do not regulate the intrinsic pumping rate. ATP regulates V-ATPase activity through the switching probability of the proton-pumping mode. By contrast, electrochemical proton gradients regulate the pumping rate and the switching of the pumping and inactive modes. A direct consequence of mode-switching is all-or-none stochastic fluctuations in the electrochemical gradient of synaptic vesicles that would be expected to introduce stochasticity in proton-driven secondary active loading of neurotransmitters and may thus have important implications for neurotransmission. This work reveals and emphasizes the mechanistic and biological importance of ultraslow mode-switching.

The broad-based coalition necessary for the care of chronically mentally disabled patients in the community consists of diverse elements and proceses that require system management as well as case management.

The objective of this lesson is to introduce fifth- and sixth-grade students to ratio and proportion through a discovery situation. This approach would also be applicable for junior and senior high general mathematics students. This technique should allow students to find patterns that will enable them to verbalize algorithms for the solution of proportions. The following is from an actual demonstration with fifth graders.