362 research outputs found
Ovulatory and metabolic effects of D-chiro-inositol in the polycystic ovary syndrome
BACKGROUND
Women with the polycystic ovary syndrome have insulin resistance and hyperinsulinemia, possibly because of a deficiency of a d-chiro-inositol–containing phosphoglycan that mediates the action of insulin. We hypothesized that the administration of d-chiro-inositol would replenish stores of the mediator and improve insulin sensitivity. METHODS
We measured steroids in serum and performed oral glucose-tolerance tests before and after the oral administration of 1200 mg of d-chiro-inositol or placebo once daily for six to eight weeks in 44 obese women with the polycystic ovary syndrome. The serum progesterone concentration was measured weekly to monitor for ovulation. RESULTS
In the 22 women given d-chiro-inositol, the mean (±SD) area under the plasma insulin curve after the oral administration of glucose decreased from 13,417±11,572 to 5158±6714 μU per milliliter per minute (81±69 to 31±40 nmol per liter per minute) (P=0.007; P=0.07 for the comparison of this change with the change in the placebo group); glucose tolerance did not change significantly. The serum free testosterone concentration in these 22 women decreased from 1.1±0.8 to 0.5±0.5 ng per deciliter (38±28 to 17±17 pmol per liter) (P=0.006 for the comparison with the change in the placebo group). The women\u27s diastolic and systolic blood pressure decreased by 4 mm Hg (Pchiro-inositol ovulated, as compared with 6 of the 22 women in the placebo group (P\u3c0.001). CONCLUSIONS
d-Chiro-inositol increases the action of insulin in patients with the polycystic ovary syndrome, thereby improving ovulatory function and decreasing serum androgen concentrations, blood pressure, and plasma triglyceride concentrations
Genetic Influences on Receptive Joint Attention in Chimpanzees (Pan troglodytes)
Despite their genetic similarity to humans, our understanding of the role of genes on cognitive traits in chimpanzees remains virtually unexplored. Here, we examined the relationship between genetic variation in the arginine vasopressin V1a receptor gene (AVPR1A) and social cognition in chimpanzees. Studies have shown that chimpanzees are polymorphic for a deletion in a sequence in the 59 flanking region of the AVPR1A, DupB, which contains the variable RS3 repetitive element, which has been associated with variation in social behavior in humans. Results revealed that performance on the social cognition task was significantly heritable. Furthermore, males with one DupB1 allele performed significantly better and were more responsive to socio-communicative cues than males homozygous for the DupB- deletion. Performance on a non-social cognition task was not associated with the AVPR1A genotype. The collective findings show that AVPR1A polymorphisms are associated with individual differences in performance on a receptive joint attention task in chimpanzees
Distal communication by chimpanzees (Pan troglodytes): evidence for common ground?
van der Goot et al. (2014) proposed that distal, deictic communication indexed the appreciation of the psychological state of a common ground between a signaler and a receiver. In their study, great apes did not signal distally, which they construed as evidence for the human uniqueness of a sense of common ground. This study exposed 166 chimpanzees to food and an experimenter, at an angular displacement, to ask, “Do chimpanzees display distal communication?” Apes were categorized as (a) proximal or (b) distal signalers on each of four trials. The number of chimpanzees who communicated proximally did not statistically differ from the number who signaled distally. Therefore, contrary to the claim by van der Goot et al., apes do communicate distally
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Formulation Efforts for Direct Vitrification of INEEL Blend Calcine Waste Simulate: Fiscal Year 2000
This report documents the results of glass formulation efforts for Idaho National Engineering and Environmental Laboratory (INEEL) high level waste (HWL) calcine. Two waste compositions were used during testing. Testing started by using the Run 78 calcine composition and switched to simulated Blend calcine composition when it became available. The goal of the glass formulation efforts was to develop a frit composition that will accept higher waste loading that satisfies the glass processing and product acceptance constraints. 1. Melting temperature of 1125 ? 25?C 2. Viscosity between 2 and 10 Pa?s at the melting temperature 3. Liquidus temperature at least 100?C below the melting temperature 4. Normalized release of B, Li and Na each below 1 g/m2 (per ASTM C 1285-97) Glass formulation efforts tested several frit compositions with variable waste loadings of Run 78 calcine waste simulant. Frit 107 was selected as the primary candidate for processing since it met all process and performance criteria up to 45 mass% waste loading. When the simulated Blend calcine waste composition became available Frits 107 and 108 compositions were retested and again Frit 107 remained the primary candidate. However, both frits suffered a decrease in waste loading when switching from the Run 78 calcine to simulated Blend calcine waste composition. This was due to increase concentrations of both F and Al2O3 along with a decrease in CaO and Na2O in the simulate Blend calcine waste all of which have strong impacts on the glass properties that limit waste loading of this type of waste
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DATA PACKET FOR THE FRIT 202-A11 SB3 GLASS SYSTEM A CANDIDATE FOR THE COLD CRUCIBLE INDUCTION MELTER DEMONSTRATION
A demonstration of the Cold Crucible Induction Melter (CCIM) technology is currently planned for the fall of 2007 to assess the potential for attaining higher waste throughputs as compared to joule heated melter technology. The CCIM demonstrations will be based on a Defense Waste Processing Facility (DWPF) waste slurry feed surrogate with a nominal operating temperature of approximately 1250 C (higher temperatures may be used). The waste slurry feed (nominally 45-50 weight percent solids) surrogate will be representative of Sludge Batch 3 (SB3) in order to allow a direct comparison to the DWPF joule heated melter performance during processing of this sludge waste. This pilot scale demonstration is being conducted to evaluate performance and to identify potential processing issues with the existing CCIM technology, and it will include characterization of the resultant glass product to ensure current product performance (durability) specifications are met. The information presented in this data packet provides a technical basis from which decisions regarding the melter demonstration can be made. More specifically, the results presented in this report provide technical data on the impact of waste loading (WL) on critical properties of interest--in particular, durability, liquidus temperature, and viscosity. All of the glasses of this study, regardless of heat treatment, were acceptable when their durabilities were compared to those of the Environmental Assessment (EA) glass. In general, as WL increases, the durabilities for the quenched versions of the glasses tend to decrease due to the changing composition of the glass. For the glasses subjected to the canister centerline cooling (ccc) regime, the durability response appears to be more non-linear as WL increases. At WLs less than 50%, X-ray diffraction (XRD) analysis indicates the potential for the presence of aegirine and/or nepheline crystalline phases, and when these phases are present, there is a decrease in the durability of the glass. As WL is increased above 50%, there is a transition from the aegirine and/or nepheline phases to a spinel phase field leading to more durable glasses. The results for durability suggest that WLs of 50% or greater should be targeted for the CCIM demonstration, thus, avoiding the potential for the formation of aegirine and/or nepheline. However, if decisions to target WLs of 50% or greater are made, liquidus temperature (T{sub L}) measurements indicate that there could be some degree of crystallization within the melter if a nominal 1250 C temperature is used. It is also anticipated that increasing WLs will lead to higher T{sub L}'s. Specifically, the T{sub L} of the 50% WL glass (HTLG-21) was measured to be slightly above 1250 C. To minimize the potential of crystallization during processing, higher melt temperatures could be targeted which not only could allow for higher WLs to be obtained but will also result in a reduction in viscosity, which in itself could pose certain processing issues (the ability to control the pour and the possibility of increased volatility). The viscosity of the 50% WL glass at 1250 and 1300 C was measured to be 20 and 13 Poise, respectively. Thus, a balance between processing and product performance issues may be required for the initial CCIM demonstrations since the frit development efforts to date were not necessarily intended to optimize this glass system nor have these efforts accounted for the variation from the intended target that is likely to occur in the composition of the waste slurry feed surrogate that is being used in the study
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HIGH LEVEL WASTE (HLW) SLUDGE BATCH 4 (SB4) WITH FRIT 418: RESULTS OF A PHASE II VARIABILITY STUDY
In early October 2006, the Liquid Waste Organization (LWO) began to consider decanting Tank 40 at the end of Sludge Batch 3 (SB3) processing and transferring the aqueous phase from the decant to Tank 51. This transfer would be done to remove water added to Tank 40 by a slurry pump bearing water leak. Tank 40 decant water would be used to decrease Tank 51 yield stress and facilitate a transfer of Tank 51 to Tank 40. The projected composition of Sludge Batch 4 (SB4) was adjusted by LWO to reflect the impact of the Tank 40 decant leading to new projected compositions for SB4, designated as the 10-04-06 and the 10-10-06 compositions. A comparison between these SB4 compositions and those provided in June 2006 indicated that the new compositions are slightly higher in Al2O3, Fe2O3, and U3O8 and slightly lower in SiO2. The most dramatic change, however, is the new projection's Na2O concentration, which is more than 4.5 wt% lower than the June 2006 projection. This is a significant change due to the frit development team's approach of aligning the Na2O concentration in a candidate frit to the Na2O content of the sludge. Questions surfaced regarding the applicability of Frit 503 to these revised compositions since the Savannah River National Laboratory (SRNL) recommended Frit 503 for use with SB4 based on the June 2006 compositional projection without the Tank 40 decant. Based on paper study assessments, the change in SB4's expected Na2O content had a significant, negative impact on the projected operating window for the Frit 503/SB4 glass system. Frit 418 had a slightly larger operating window for the 10-04-06 projection (as compared to a lower Na2O frit, Frit 503) and the Frit 418/10-04-06 glass system was no longer nepheline limited. Thus, strictly from the perspective of this paper study, Frit 418 was more attractive than Frit 503 for the new SB4 projected compositions. This comparison, however, did not reflect other aspects of interest for the glass systems such as their respective melt rates or the development of alternative frits to balance the projected operating windows, melt rate, waste throughput, and robustness to compositional variation. In discussions with Waste Solidification Engineering (WS-E) regarding the paper study results, their decision was to utilize Frit 418 for initial processing of SB4. This decision was not only based on the paper study assessments, but also on the fact that Frit 418 is currently being used to process SB3 and, perhaps more importantly, frit optimization efforts for SB4 may be premature given the uncertainties in tank transfers, volumes, and any operational issues associated with the decant transfer from Tank 40 to Tank 51 and the sludge transfer from Tank 51 to Tank 40. Given this decision and recognizing that a SB4/Frit 503 variability study had been initiated as part of the qualification process, questions regarding the need for a supplemental variability study to demonstrate applicability of the process control models for a Frit 418 based system surfaced. In response to the change in the projected composition for SB4 and the selection of Frit 418 by WS-E, SRNL complemented the SB4/Frit 503 variability study with 13 additional glasses using Frit 418. The composition region for the new glasses (or the SB4/Frit 418 variability study) was determined using the October 2006 projections of the SB4 composition
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SLUDGE BATCH 5 (SB5): SELECTION OF CANDIDATE FRITS AND CHARACTERIZATION OF PRELIMINARY GLASS SYSTEMS
Six potential frits were identified as candidates for processing the February 2007 projected SB5 composition (i.e., no implementation of aluminum dissolution) from an array of frit formulations based upon composition-property model predictions. Test glasses were fabricated in the laboratory to verify the applicability of the product performance models to glasses produced with these frits. Characterization of the glasses fabricated with the selected frits showed that all of the glasses had durability responses that are considered very acceptable at a waste loading of 36%. The durability responses were predictable by the free energy of hydration models. No crystallization was identified in the quenched glasses. Samples of the glasses that were slowly cooled following the canister centerline cooled (ccc) thermal profile were found to contain small amounts of magnetite. This crystalline phase had little impact on the durability of the glasses, and therefore is not an issue for concern based on the February 2007 projections. Note that revised versions of the SB5 flowsheet, including those incorporating aluminum dissolution, are expected, which will require additional frit development work when received. Initial melt rate testing results showed that the previously identified trend of increasing melt rate with increasing concentration of B2O3 for SB4 may be extended to this SB5 system. A complete report on melt rate testing with these frits will be issued at a later date
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INITIAL SLUDGE BATCH 4 TANK 40 DECANT VARIABILITY STUDY WITH FRIT 510
Sludge Batch 4 (SB4) is currently being processed in the Defense Waste Processing Facility (DWPF) using Frit 510. The slurry pumps in Tank 40 are experiencing in-leakage of bearing water, which is causing the sludge slurry feed in Tank 40 to become dilute at a rapid rate. Currently, the DWPF is removing this dilution water by performing caustic boiling during the Sludge Receipt and Adjustment Tank (SRAT) cycle. In order to alleviate prolonged SRAT cycle times that may eventually impact canister production rates, decant scenarios of 100, 150, and 200 kilogallons of supernate were proposed for Tank 40 during the DWPF March outage. Based on the results of the preliminary assessment issued by the Savannah River National Laboratory (SRNL), the Liquid Waste Organization (LWO) issued a Technical Task Request (TTR) for SRNL to (1) perform a more detailed evaluation using updated SB4 compositional information and (2) assess the viability of Frit 510 and determine any potential impacts on the SB4 system. As defined in the TTR, LWO requested that SRNL validate the sludge--only SB4 flowsheet and the coupled operations flowsheet using the 100K gallon decant volume as well as the addition of 3 wt% sodium on a calcined oxide basis. Approximately 12 historical glasses were identified during a search of the ComProTM database that are located within at least one of the five glass regions defined by the proposed SB4 flowsheet options. While these glasses meet the requirements of a variability study there was some concern that the compositional coverage did not adequately bound all cases. Therefore, SRNL recommended that a supplemental experimental variability study be performed to support the various SB4 flowsheet options that may be implemented for future SB4 operations in DWPF. Eighteen glasses were selected based on nominal sludge projections representing the current as well as the proposed flowsheets over a WL interval of interest to DWPF (32-42%). The intent of the experimental portion of the variability study is to demonstrate that the glasses of the Frit 510-modified SB4 compositional region (Cases No.1-5) are both acceptable relative to the Environmental Assessment (EA) reference glass and predictable by the current DWPF process control models for durability. Frit 510 is a viable option for the processing of SB4 after a Tank 40 decant and the addition of products from the Actinide Removal Process (ARP). The addition of ARP did not have any negative impacts on the acceptability and predictability of the variability study glasses. The results of the variability study indicate that all of the study glasses (both quenched and centerline canister cooled (ccc)) have normalized releases for boron that are well below the reference EA glass (16.695 g/L). The durabilities of all of the study glasses are predictable using the current Product Composition Control System (PCCS) durability models with the exception of SB4VAR24ccc (Case No.2 at 41%). PCCS is not applicable to non-homogeneous glasses (i.e. glasses containing crystals such as acmite and nepheline), thus SB4VAR24ccc should not be predictable as it contains nepheline. The presence of nepheline has been confirmed in both SB4VAR13ccc and SB4VAR24ccc by X-ray diffraction (XRD). These two glasses are the first results which indicate that the current nepheline discriminator value of 0.62 is not conservative. The nepheline discriminator was implemented into PCCS for SB4 based on the fact that all of the historical glasses evaluated with nepheline values of 0.62 or greater did not contain nepheline via XRD analysis. Although these two glasses do cause some concern over the use of the 0.62 nepheline value for future DWPF glass systems, the impact to the current SB4 system is of little concern. More specifically, the formation of nepheline was observed in glasses targeting 41 or 42% WL. Current processing of the Frit 510-SB4 system in DWPF has nominally targeted 34% WL. For the SB4 variability study glasses targeting these lower WLs, nepheline formation was not observed and the minimal difference in PCT response between quenched and ccc versions supported its absence
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VARIABILITY STUDY WITH FRIT 510 TO SUPPORT A SECOND TANK 40 DECANT
Sludge Batch 4 (SB4) is currently being processed in the Defense Waste Processing Facility (DWPF) using Frit 510. The slurry pumps in Tank 40 are experiencing in-leakage of bearing water, which is causing the sludge slurry in Tank 40 to become dilute at a rapid rate. Currently, the DWPF is removing this dilution water by performing caustic boiling during the Sludge Receipt and Adjustment Tank (SRAT) cycle. In order to alleviate prolonged SRAT cycle times, which may eventually impact canister production rates, the Liquid Waste Organization (LWO) performed a 100K gallon supernate decant of Tank 40 in April 2008. SRNL performed a supplemental glass variability study to support the April 2008 100K gallon decant incorporating the impact of coupled operations (addition of the Actinide Removal Process (ARP) stream). Recently LWO requested that SRNL assess the impact of a second decant (up to 100K gallon) to the Frit 510-SB4 system. This second decant occurred in June 2008. LWO provided nominal compositions on May 6, 2008 representing Tank 40 prior to the second decant, following the second decant, and the SB4 Heel prior to blending with Tank 51 to constitute SB5. Paper study assessments were performed for these options based on sludge-only and coupled operations processing (ARP addition), as well as possible Na{sub 2}O additions (via NaOH additions) to both flowsheets. A review of the ComProTM database relative to the compositional region defined by the projections after the second decant coupled with Frit 510 identified only a few glasses with similar glass compositions. These glasses were acceptable from a durability perspective, but did not sufficiently cover the new glass compositional region. Therefore, SRNL recommended that a supplemental variability study be performed to support the June 2008 Tank 40 decant. Glasses were selected for the variability study based on three sludge compositional projections (sludge-only, coupled and coupled + 2 wt% Na{sub 2}O) at waste loadings (WLs) of interest to DWPF (32%, 35% and 38%). These nine glasses were fabricated and characterized using chemical composition analysis, X-ray Diffraction (XRD) and the Product Consistency Test (PCT). All of the glasses that were selected for this study satisfy the Product Composition Control System (PCCS) criteria and are deemed processable and acceptable for the DWPF, except for the SB4VS2-03 (sludge-only at 38% WL) target composition. This glass fails the T{sub L} criterion and would not be considered processable based on Slurry Mix Evaporator (SME) acceptability decisions. The durabilities of all of the study glasses (both quenched and ccc) are well below that of the normalized leachate for boron (NL [B]) of the reference EA glass (16.695 g/L) and are predictable using the current PCCS models. Very little variation exists between the NL [B] of the quenched and ccc versions of the glasses. There is some evidence of a trend toward a less durable glass as WL increases for some of the sludge projections. Frit 510 is a viable option for the processing of SB4 after a second Tank 40 decant with or without the addition of products from the ARP stream as well as the 2 wt% Na{sub 2}O addition. The addition of ARP had no negative impacts on the acceptability and predictability of the variability study glasses
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