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1. We tested the hypothesis thatGerbillus henleyi(de Winton 1903), the smallest species (10 g) of a pssamophilic guild in Israel, is scarce on relatively productive dunes of the Israeli desert, due to negative interactions from the commonG. allenbyi (Thomas 1918) andG. pyramidum(Geoffroy 1825).2. The alternative hypothesis was that scarcity on sand resulted from the size of its naked hind feet, that do not allow efficient locomotion on sand.3. Despite their naked soles the weight-bearing surface ofG. henleyifeet carry less mass/area than those of any other species.4. We measured interaction coefficients with the two common species using field-manipulation experiments in two enclosures.5. Habitat usage ofG. henleyichanged from significantly preferring the stabilized sand, when alone, to significantly using the semistabilized dune, whenG. allenbyiwas also present.6. We also estimated the interaction coefficients and calculated theG. henleyi's isoclines competing with the two common gerbil species using a technique we developed elsewhere.7. The stability analysis of the isoclines ofG. henleyicompeting with eitherG. allenbyior withG. pyramidumsuggests that stable coexistence occurs whenG. henleyiis relatively scarce while the competitors are common.8. Interspecific competition from eitherG. allenbyiorG. pyramidumaccounts for 90·3% reduction inG. henleyidensity, relative to when it is alone.9. We concluded that the negative interactions from congeners was the major cause for the scarcity ofG. henleyion the relatively rich sand dunes of the Israeli desert.Journal of Animal Ecology(2005)74, 567–578doi: 10.1111/j.1365-2656.2005.00956.x [ABSTRACT FROM AUTHOR]

PURPOSE: To describe three commercial weight loss programs (Jenny Craig, LA Weight Loss, and Weight Watchers), including efficacy data when available, and to provide clinicians with information for patient counseling. DATA SOURCES: Personal interviews, journal articles, and Web site information. CONCLUSIONS: Commercial weight loss programs provide weight loss services. Benefits are experience, planned menus, and psychological support. Limitations are cost, sales promotions that encourage on-the-spot commitment to prepaid contracts, and the cost of program food and additional vitamins. IMPLICATIONS FOR PRACTICE: Weight loss is a necessary goal for many patients. Clinicians are mandated to provide counseling regarding weight loss. [ABSTRACT FROM AUTHOR]

Ecologists need not despair of discovering the mechanisms that lead to large scale patterns. The search for process at higher scales has already led to enhanced confidence in the patterns and to improvements in their description. For example, species-area relationships turn out to form not one, but three patterns. Each is controlled by gain-loss dynamics at its own scale. At the macroscale, origination and global extinction reign. At the archipelagic scale, immigration and island extinction determine the results. At the local scale, metapopulation processes do. The three scales exhibit species-area curves with systematically different slopes in logarithmic space. We use the three scales of species-area to illuminate the relationship between local and regional diversity. Algebra shows that the latter pattern is an echo of species-area curves, and that those echoes ought to be nearly linear. So, we call the relationship of local and regional diversity, the Echo pattern. Ecology has long known that species-area curves within a region reflect the accumulation of habitat variety. Thus, theirconnection to Echo patterns argues against concluding that local diversity has little or nothing to do with population interactions. To obtain a pure Echo pattern, one should draw data from independent regions rather than separate islands. The independence allows natural selection to adjust the fundamental niches of species to diversity. Theory suggests that higher diversity should shrink niches, allowing the coexistence of more species locally. Hence, independence should tend to produce the straightest Echoes. However, archipelagic species-areacurves predict that even when different islands are used as the regions, the Echoes should show only very gentle curvatures. Flouting theory, some archipelagic Echoes approach an asymptote as regional diversity increases. These must have logarithmic slopes that increase withregional pool size. We do not understand why. [ABSTRACT FROM AUTHOR]

Presents a study which examines the behavior, heterogeneity and the dynamics of interacting species. Behavior and dynamics; Heterogeneity, behavior and dynamics; Conclusions.

We have discovered a severe problem with the current theory of species-area curves (SPARs). This theory claims that we should expect SPARs with z-values of about 0.26. However, that is wrong. The correct prediction turns out to be approximately 0.77. To make this prediction,we used a stochastic sampling scheme, and constructed species-area curves from a lognormal abundance distribution, exactly as previous theory meant to do. We arrived at our prediction using two independent methods: we performed computer simulations of the scheme and we derived its analytical equation. SPARs that result from the simulations are the same as those from the equation, validating the logic of our analysis. We explain what went awry with the previous theory. However, although logically accurate, the new theory has an empirical problem:real SPARs do not have z-values near 0.77. Rather. they tend to lie in the interval 0.1--0.2. To obtain these, we added an assumption to the lognormal abundance distribution. We assumed that range size and abundance are positively correlated. This new assumption is qualitatively similar to Hanski's (1982; Oikos 38: 210-221) pattern. Finally, we derive a simple relation connecting average point diversity, average range size and species diversity for a province. [ABSTRACT FROM AUTHOR]

We trained barn owls to fly over 2-ha field enclosures containing populations of Gerbillus allenbyi. Each 2-ha plot was divided into two equal parts by a fence with gates allowing easy passage of the gerbils. We varied the number of gerbils in the enclosure and the number ofowl flights on each side of the dividing fence. Gerbil foraging activity responded within two hours to the difference in number of owl flights over the subplots. The greater the difference, the more the gerbils shifted their foraging to the subplot with fewer flights. Gerbils did not reduce their total foraging effort but redistributed it between subplots. In the absence of owl flights, gerbils divided their foraging effort equally between the matched subplots. Thus, they appear to seek an ideal free distribution in the two halves of each plot. Therefore, based on the gerbils' distribution of activity in the presence of different numbers of owl flights over the two subplots we estimated the shapes and slopes of the gerbil victim isoclines in the middle and right hand side of the 'gerbil-activity vs number of owl flights' state space. The isoclines were parallel straight lines with slope equal to -0.57. We believe this to be the first estimate of a victim isocline for a population of vertebrates in the field. Using the isodar method of Morris, we also determined that the fitness cost of each additional gerbil, i.e., per capita intraspecific competition among the G. allenbyi, is constant. It does not depend on either owl flight frequencies or G. allenbyi densities. The isodar also shows thatthe fitness cost of added owl flights does not vary with G. allenbyipopulation densities. [ABSTRACT FROM AUTHOR]

In the phase 3 ANDROMEDA trial, patients treated with daratumumab, bortezomib, cyclophosphamide, and dexamethasone (D-VCd) had significantly higher rates of organ and hematologic response compared with patients who received VCd alone. Here, we present patient-reported outcomes (PROs) from the ANDROMEDA trial. PROs were assessed through cycle 6 using three standardized questionnaires. Treatment effect through cycle 6 was measured by a repeated-measures, mixed-effects model. The magnitude of changes in PROs versus baseline was generally low, but between-group differences favored the D-VCd group. Results were generally consistent irrespective of hematologic, cardiac, or renal responses. More patients in the D-VCd group experienced meaningful improvements in PROs; median time to improvement was more rapid in the D-VCd group versus the VCd group. After cycle 6, patients in the D-VCd group received daratumumab monotherapy and their PRO assessments continued, with improvements in health-related quality of life (HRQoL) reported through cycle 19. PROs of subgroups with renal and cardiac involvement were consistent with those of the intent-to-treat population. These results demonstrate that the previously reported clinical benefits of D-VCd were achieved without decrement to patients' HRQoL and provide support of D-VCd in patients with AL amyloidosis., (© 2022 Wiley Periodicals LLC.)