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In this paper we analyze four examples of birational transformations between local Calabi-Yau 3-folds: two crepant resolutions, a crepant partial resolution, and a flop. We study the effect of these transformations on genus-zero Gromov-Witten invariants, proving the Coates-Corti-Iritani-Tseng/Ruan form of the Crepant Resolution Conjecture in each case. Our results suggest that this form of the Crepant Resolution Conjecture may also hold for more general crepant birational transformations. They also suggest that Ruan's original Crepant Resolution Conjecture should be modified, by including appropriate "quantum corrections", and that there is no straightforward generalization of either Ruan's original Conjecture or the Cohomological Crepant Resolution Conjecture to the case of crepant partial resolutions. Our methods are based on mirror symmetry for toric orbifolds., 27 pages. This is a substantially revised and shortened version of my preprint "Wall-Crossings in Toric Gromov-Witten Theory II: Local Examples"; all results contained here are also proved there. To appear in Communications in Mathematical Physics

If a monoid S is given by some finite complete presentation ℘, we construct inductively a chain of CW-complexes $$\mathcal{D}\subset \Delta_{2}\subset(\mathcal{D},\mathbf{p}_{1})\subset\Delta_{3}\subset \cdots\subset \Delta_{n-1}\subset (\mathcal{D},\mathbf{p}_{1},\ldots,\mathbf{p}_{n-2})\subset \Delta_{n},$$ such that Δn has dimension n, for every 2≤m≤n, the m-skeleton of Δn is Δm, and pm are critical (m+1)-cells with 1≤m≤n−2. For every 2≤m≤n−1, the following is an exact sequence of (ℤS,ℤS)-bimodules $$0\rightarrow H_{m}(\mathcal{D},\mathbf{p}_{1},\ldots,\mathbf{p}_{m-1})\stackrel{\Phi }{\longrightarrow}\mathbb{Z}S.\mathbf{p}_{m-1}.\mathbb{Z}S\stackrel{\nu}{\longrightarrow }H_{m-1}(\mathcal{D},\mathbf{p}_{1},\ldots,\mathbf{p}_{m-2})\rightarrow 0,$$ where \((\mathcal{D},\mathbf{p}_{1},\ldots,\mathbf{p}_{m-2})=\mathcal{D}\) if m=2. We then use these sequences to obtain a free finitely generated bimodule partial resolution of ℤS. Also we show that for groups properties FDT and FHT coincide.

The present studies were undertaken to examine the effects of manipulating delay-interval task (Study 1) and timing of feedback (Study 2) on acquisition and retention. Participants completed a 100-item cumulative final examination, which included 50 items from each laboratory examination, plus 50 entirely new items. Acquisition and retention were examined in Study 1 in which delayinterval task, length of delay until feedback was delivered, and the opportunity to answer until correct (AUG) were manipulated and, in Study 2, in which the number of items completed before feedback was delivered and AUC were manipulated. Delays longer than 5 s negatively affected learning (Study 1) when participants engaged in a delay-interval distraction task; enhancement was observed when individual test items and correct responses were reviewed during the interval. Significant decrements in learning were observed in Study 2 in the absence of a distraction task when more than 1 test item was completed prior to the delivery of feedback. The present outcomes add to the growing body of evidence that retention is maximized when test items are completed individually and exited with knowledge of the correct response, that the opportunity to answer until correct minimizes perseverative inaccurate responding and, for multiple-choice test items, that immediate feedback is a more effective facilitator of retention than delayed feedback.

We generalize the concept of an incomplete double group divisible design and describe some recursive constructions for such a generalized new design. As a consequence, we obtain a general recursive construction for group divisible designs, which unifies many important recursive constructions for various types of combinatorial designs. We also introduce the concept of a double frame. After providing a preliminary result on the number of partial resolution classes, we describe a general construction for double frames. This construction method can unify many known recursive constructions for frames.

In this paper, we study the asymptotics of the spectrum of the Dirichlet (or Neumann) Laplacian in a bounded open set Ω ⊂R n (n ≥ 1) with irregular but nonfractal boundary∂Ω. We give a partial resolution of the Weyl conjecture, i.e. for the counting functionN i (λ)(i=0 : Dirichlet;i=1 : Neumann), we have got a precise estimate of the remainder term÷ i (λ)=ϕ(λ) −N i (λ) for largeλ, whereϕ(λ) is the Weyl term. This implies that for the irregular but nonfractal drum Ω, not only the volume |Ω| n is spectral invariant but also the area of boundary |∂Ω| n−1 might be spectral invariant as well.

This article is an attempt to analyze the implications for research in the human sciences of the topic of “indeterminacy”. Reviewing an aspect of the issue from the philosophy of social science, the author argues that the debates at the philosophical level often overlook or underestimate the importance of methodological approaches. While the philosophical issue of indeterminacy remains a vexing problem in the social sciences since it was raised by Quine, the article argues that at least a partial resolution of the issue is possible if it is viewed within the context if differing methodological approaches.

Studies in children showed that despite ultrasonographic resolution of nephrocalcinosis (NC) caused by furosemide (F), glomerular and tubular perturbations may persist (J. Pedr. 1992;120:563). Histologic studies in rats demonstrated only partial resolution of NC up to 12 wks after stopping F(Pedr. Nephrol 1996;10:191). In the present study we examined whether treatment with chlorothiazide (CTZ) will enhance the resolution of established F-induced NC. 4-wks old male Sprague-Dawley rats were divided into 8 groups(n=6- 12). 3 groups (a-c) were studied for 1 wk as follows: (a) controls, (b) F 40 mg/kg/24 h; (c) CTZ 100 mg/kg/24 h. 5 groups were studied for 5 weeks as follows; (d) controls; (e) (f) (g) F as in b followed by 4 wks of (e) observation (f) CTZ 50 mg/kg/24 h (g) CTZ 100 mg/kg/24 h; (h) CTZ 100 mg/kg/24 h. In the last 4 days of each study period rats were placed in metabolic cages and urine collected. At the end animals were killed, blood obtained and the kidneys harvested. One kidney was studied histologically and the other ashed for Ca analysis. Results (mean ± SD): rats in gr. b developed NC(Kidney Ca 1894±203 mcg/gm dry tissue) compared with gr. a(248±84) and gr. c (254±54). There were no differences among the 3 groups in Ccr, urine P or Ca although the latter tended to be lower in gr. c. In comparison with gr. b rats in gr. e showed lowered kidney Ca(530±398), however it was still significantly higher than in gr. d(140±27) and gr. h (162±63). There were no differences among grs. d-h in regard to Ccr and urine P; urine Ca was lower in the 3 grs. treated with CTZ compared with grs. d and e. However, kidney Ca in grs. f(497±142) and g (489±271) were not different from gr. e and higher than in grs. d and h. We conclude that despite significant reduction in urine Ca excretion CTZ therapy does not affect established F-induced NC. This result further emphasizes the need for prevention of this complication.

From an investigation of the ICD of bilatrienes-abc and 2,3-dihydrobilatrienes-abc induced by mixtures of CCl4 with (+)-cis-Pinane, (−)-lactic and (+)-tartaric acid esters it is concluded that specific interactions between chromophore and the chiral reagents afford a partial resolution of the labile racemate of helices. Attaching chiral residues covalently to the chromophore induces very low resolution of the same kind in case of apolar ligands like a cholesteryl-residue. However, with polar ligands as in the case ofBoc-lysyl derivatives enantiomeric excesses up to 90% are achieved depending on the solvent used.

1. Even when it has been cooled slowly to room temperature, annealed rimmed technically pure iron is sub ect to precipitation hardening (age hardening). After this metal has been held at room temperature for 20.000 h, or at 150°C for 300 h, the coercive force is almost doubled. 2. The coagulation of particles of the precipitated phases causes the coercive force of annealed iron to decrease to the initial value when it is heated at temperatures up to 350°C. When this is done however, particularly when the heating is for long periods, partial resolution of the phases takes place, and for this reason further heating at 150°C for 50 h again greatly increases the coercive force. Heating articles previously held at room temperature for 20,000 h, for short periods at 150–350°C causes a recovery process, and further heating for 50 h at 150°C also greatly increases the coercive force. 3. Holding annealed iron at about 250°C for 4 h stabilizes it, since in this case there is very little re-solution of phases. The coercive force proves to be about the same as after annealing. The conditions for this stabilizing treatment should, however, be found separately for each batch of iron. 4. The processes of precipitation and solution of phases in annealed iron are most rapid in the grain boundaries.

Frontier studies continue to be compromised by a double inadequacy. While geographers mistakenly cling to obsolete models of frontier process, those who have adopted a more progressive interactionist definition have difficulty conceptualizing the components and dimensions of interaction. The conceptual framework suggested by the literature on the articulation of modes of production is proposed as a partial resolution of the problem. Discarding the abstract and problematical notion of the mode of production as a useful tool for concrete analysis, attention is focused on the concepts and hypotheses suggested by the notion of articulation. It is proposed that in southern Africa, at least, this concept offers geographers a way forward which will circumvent the difficulties currently being experienced by the predominantly liberal interactionist school.

A review is presented of some of the previously reported differences and similarities between comparable gel glasses (and gels) and ordinary glasses. In this regard, considerations are made with respect to such factors as structure, physical and thermal properties, and phase transformation behavior. A variety of silicate lass compositions are used for illustrative purposes. The discussion is roughly ivided into two sections; low and high temperature behavior. At low temperatures one anticipates that differences between gel and conventional glasses will exist, but such dissimilarities are not expected to persist to high temperatures. However, experimental evidence is presented which indicates the perpetuation of such differences to very high temperatures. A partial resolution for this anomalous behavior is offered.

1. Partial resolution of racemic hydrocarbons into their antipodes was effected by introduction of seed crystals of a clathrate compound of the optically active hydrocarbon. 2. Optically active hydrocarbons and two thiophene compounds were synthesized.

IT is possible to prepare silica gels in the presence of an organic substance, for example, methyl orange, in such a manner that the dried extracted gel exhibits greater adsorptive power for the dye than a gel prepared in its absence1. A specific silica gel has been used to effect a partial resolution of camphor sulphonic acid2.

WE have found that, when a mixture containing barbiturate, salicylate and acetophenetidin is subjected to chromatography on Whatman No. DE20 cellulosic ion-exchange paper in dilute ammonia solution, a partial resolution of the components is possible. Salicylate is clearly separated from the other two compounds, which move together with only partial resolution (Fig. 1).

Comprehension of task instructions was evaluated as a possible causative factor for marked differences in previously reported distributions of RFT scores between psychiatric inpatient and college student samples. For 100 male and 118 female patients, RFT scores were examined as a function of errors on a simple four-item task instruction questionnaire. For both sexes, questionnaire errors resulted in increased field dependence, with males being significantly more field independent than females. Although RFT scores of error-free questionnaire patients more closely approximated those of college students, some differences apparently remain, requiring further empirical investigative efforts.