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To extend the MR MultiTasking-based Multidimensional Assessment of Cardiovascular System (MT-MACS) technique with larger spatial coverage and water-fat separation for comprehensive aortocardiac assessment.MT-MACS adopts a low-rank tensor image model for 7D imaging, with three spatial dimensions for volumetric imaging, one cardiac motion dimension for cine imaging, one respiratory motion dimension for free-breathing imaging, one T2-prepared inversion recovery time dimension for multi-contrast assessment, and one T2*-decay time dimension for water-fat separation. Nine healthy subjects were recruited for the 3T study. Overall image quality was scored on bright-blood (BB), dark-blood (DB), and gray-blood (GB) contrasts using a 4-point scale (0-poor to 3-excellent) by two independent readers, and their interreader agreement was evaluated. Myocardial wall thickness and left ventricular ejection fraction (LVEF) were quantified on DB and BB contrasts, respectively. The agreement in these metrics between MT-MACS and conventional breath-held, electrocardiography-triggered 2D sequences were evaluated.MT-MACS provides both water-only and fat-only images with excellent image quality (average score = 3.725/3.780/3.835/3.890 for BB/DB/GB/fat-only images) and moderate to high interreader agreement (weighted Cohen's kappa value = 0.727/0.668/1.000/1.000 for BB/DB/GB/fat-only images). There were good to excellent agreements in myocardial wall thickness measurements (intraclass correlation coefficients [ICC] = 0.781/0.929/0.680/0.878 for left atria/left ventricle/right atria/right ventricle) and LVEF quantification (ICC = 0.716) between MT-MACS and 2D references. All measurements were within the literature range of healthy subjects.The refined MT-MACS technique provides multi-contrast, phase-resolved, and water-fat imaging of the aortocardiac systems and allows evaluation of anatomy and function. Clinical validation is warranted.

Heart failure (HF) is a complex disease associated with multisystem organ failure, recurrent hospital admissions, and increased mortality. Acute decompensated heart failure (ADHF) increases central venous pressure (CVP) with resultant hepatic congestion, and this relationship has prognostic significance. The gold standard method of measuring CVP, right heart catheterization, is invasive and costly, prompting further investigation into more accurate non-invasive assessments in HF patients, including liver elastography. Liver elastography relies on imaging techniques to assess liver stiffness measurements (LSM), with high values equating to increased stiffness. While this was developed to assess fibrosis in liver disease, LSM also reflect increased CVP and hepatic congestion. Multiple studies involving ADHF patients, find that increased LSM are independently predictive of increased cardiac events, all-cause mortality, and worse post-operative outcome after both acute HF exacerbation and left ventricular assist device (LVAD) placement. In this review, we discuss the role of LSM as a surrogate for CVP and their applications in determining prognosis in both the ADHF and LVAD populations.

BACKGROUND Intra-aortic balloon pumps (IABP) are used to bridge select end-stage heart disease patients to heart transplant (HT). IABP use and exception requests both increased dramatically after the UNOS policy change (PC). The purpose of this study was to evaluate the effect of PC and exception status requests on waitlist and post-transplant outcomes in patients bridged to HT with IABP support. METHODS We analyzed adult, first-time, single-organ HT recipients from the UNOS Registry either on IABP at the time of registration for HT or at the time of HT. We compared waitlist and post-HT outcomes between patients from the PRE (October 18, 2016 to May 30, 2018) and POST (October 18, 2018 to May 30, 2020) eras using Kaplan-Meier curves and time-to-event analyses. RESULTS A total of 1267 patients underwent HT from IABP (261 pre-policy/1006 post-policy). On multivariate analysis, PC was associated with an increase in HT (sub-distribution hazard ratio (sdHR): 2.15, p

Many questions relevant to conservation decision‐making are characterized by extreme uncertainty due to lack of empirical data and complexity of the underlying ecologic processes, leading to a rapid increase in the use of structured protocols to elicit expert knowledge. Published ecologic applications often employ a modified Delphi method, where experts provide judgments anonymously and mathematical aggregation techniques are used to combine judgments. The Sheffield elicitation framework (SHELF) differs in its behavioral approach to synthesizing individual judgments into a fully specified probability distribution for an unknown quantity. We used the SHELF protocol remotely to assess extinction risk of three subterranean aquatic species that are being considered for listing under the U.S. Endangered Species Act. We provided experts an empirical threat assessment for each known locality over a video conference and recorded judgments on the probability of population persistence over four generations with online submission forms and R‐shiny apps available through the SHELF package. Despite large uncertainty for all populations, there were key differences between species’ risk of extirpation based on spatial variation in dominant threats, local land use and management practices, and species’ microhabitat. The resulting probability distributions provided decision makers with a full picture of uncertainty that was consistent with the probabilistic nature of risk assessments. Discussion among experts during SHELF's behavioral aggregation stage clearly documented dominant threats (e.g., development, timber harvest, animal agriculture, and cave visitation) and their interactions with local cave geology and species’ habitat. Our virtual implementation of the SHELF protocol demonstrated the flexibility of the approach for conservation applications operating on budgets and time lines that can limit in‐person meetings of geographically dispersed experts., Article Impact Statement: Remote expert elicitation can facilitate endangered species decision‐making when available data, budgets, and time frames are limiting.

Aims Hyponatremia is associated with poorer outcomes and diuretic response in patients hospitalized for heart failure. This study compared a tolvaptan‐based vs. furosemide‐based diuretic regimen on short‐term clinical responses in hyponatremic acute heart failure. Methods and results Prospective, randomized, open‐label, parallel‐group, single‐centre study comparing oral tolvaptan vs. continuous infusion furosemide. Thirty‐three subjects requiring hospitalization for acute congestive heart failure, and a serum sodium

BACKGROUND Heated and humidified high flow nasal cannula oxygen therapy has been used in children with severe bronchiolitis. No data exists in children with mild to moderate bronchiolitis requiring lower flows of heated and humidified oxygen therapy. METHODS We conducted a prospective, randomized pilot study of standard dry oxygen (control) versus heated and humidified low flow nasal cannula (HHLFNC)

Purpose To determine the feasibility of measuring increases in myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) on a per-segment basis using arterial spin labeled (ASL) magnetic resonance imaging (MRI) with adenosine vasodilator stress in normal human myocardium. Materials and Methods Myocardial ASL scans at rest and during adenosine infusion were incorporated into a routine 3T MR adenosine-induced vasodilator stress protocol and were performed in 10 healthy human volunteers. Myocardial ASL was performed using single-gated flow-sensitive alternating inversion recovery (FAIR) tagging and balanced steady-state free precession (bSSFP) imaging at 3T. A T2-prep blood oxygen level-dependent (BOLD) SSFP sequence was used to concurrently assess segmental myocardial oxygenation with BOLD signal intensity (SI) percent change in the same subjects. Results There was a statistically significant difference between MBF measured by ASL at rest (1.75 ± 0.86 ml/g/min) compared to adenosine stress (4.58 ± 2.14 ml/g/min) for all wall segments (P < 0.0001), yielding a per-segment MPR of 3.02 ± 1.51. When wall segments were divided into specific segmental myocardial perfusion territories (ie, anteroseptal, anterior, anterolateral, inferolateral, inferior, and inferoseptal), the differences between rest and stress regional MBF for each territory remained consistently statistically significant (P < 0.001) after correcting for multiple comparisons. Conclusion This study demonstrates the feasibility of measuring MBF and MPR on a segmental basis by single-gated cardiac ASL in normal volunteers. Second, this study demonstrates the feasibility of performing the ASL sequence and T2-prepared SSFP BOLD imaging during a single adenosine infusion. Level of Evidence: 2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:413–420

In some environments, species may exhibit trophic plasticity, which allows them to extend beyond their assigned functional group. For Gammarus minus, a freshwater amphipod classified as a shredder or detritivore, cave populations have been observed consuming heterotrophs as well as shredding leaves, and therefore may be exhibiting trophic plasticity. To test this possibility, we examined the C and N stable isotope and C/N ratios for cave and spring populations of G. minus. A 15-day feeding experiment using leaves and G. minus from a spring population established that the diet-tissue discrimination factor was 3.2 ‰ for δ15N. Cave G. minus were 8 ‰ higher in δ15N relative to cave leaves, indicating they did not derive nitrogen from leaves, whereas field collected spring populations were 2–3 ‰ higher than spring leaves, indicating that they did. Cave G. minus were 2.6 ‰ higher in δ15N than the cave isopod, Caecidotea holsingeri. Relative to spring populations, Organ Cave G. minus were 15N enriched by 6 ‰, suggesting they occupied a different trophic level, or incorporated an isotopically distinct N source. While stable isotopes cannot tell what the cave G. minus are eating, the isotopes certainly show that G. minus are not eating leaves and are trophically distinct form the surface populations. Differences in C/N ratios were observed, but reflect the size of the G. minus examined and not feeding group or habitat. The isotope data strongly support the hypothesis that cave populations of G. minus have become generalist or omnivorous by including animal protein in their diet.

Background Both laparoscopic and robotic hepatectomy have been adopted in our centre for selected patients with benign or malignant liver diseases. This article reports the perioperative outcomes of these two approaches and tries to determine any difference between them. Methods A retrospective review of prospectively collected data was performed for all patients who underwent laparoscopic hepatectomy (LH) and robotic hepatectomy (RH) in our institute. The perioperative results were reported and compared. In order to standardise the type of liver resection performed, a subgroup analysis was made for laparoscopic left lateral sectionectomy (LS) and robotic left lateral sectionectomy (RS). Results Sixty-six LH and 70 RH were performed between November 2003 and January 2015. The two groups were comparable in demographic data and disease characteristics except more patient with recurrent pyogenic cholangitis (RPC) occurred in RH group. More major hepatectomies were performed in RH (20.0% versus 3.0%, P = 0.002). There was no mortality. No difference was noted in morbidity (LH 4.5%, RH 11.4%), conversion rate (LH 12.1%, RH 5.7%), median blood loss (both 100 mL) and median length of post-operative hospital stay (both 5 days) but operative time was longer in RH (251.5 min versus 215 min, P = 0.008). There were 29 LS and 38 RS, no difference was noted in all perioperative outcomes between the two groups. Conclusion Both laparoscopic and robotic hepatectomy are safe and their perioperative outcomes are comparable and favourable.

The resilience of parents of people with intellectual disability (ID) has increasingly become a concern in the field. However, very little research has focused on resilience interventions. In Hong Kong, the authors attempted to enhance the resilience level of parents of adults with ID through their participation in a volunteer program. The purpose of this study was to investigate the relationships between participation in the volunteer program and the resilience protective factors of parents. A pretest–posttest design was used involving 36 of the participants who were recruited from the 6-month volunteer program. A 24-item Resilience Measuring Scale developed from the Resilience Scale and the Purpose in Life Test was used to measure the changes in the participants after the intervention. The results showed that the participants achieved positive changes in the protective factors of social resources and meaning of life after joining the volunteer program. The findings provide initial evidence of the relationship between volunteering and the resilience protective factors for middle- to old-aged Chinese parents. The factors of the program that facilitated resilience enhancement included using a group format, providing a situation to appreciate problems that others have, and frequent debriefings enabling integration and internalization of the experience. The authors posit some implications on the interventions for this population and make recommendations for further studies.

A highly sensitive single-walled carbon nanotube/C60 -based infrared photo-transistor is fabricated with a responsivity of 97.5 A W(-1) and detectivity of 1.17 × 10(9) Jones at 1 kHz under a source/drain bias of -0.5 V. The much improved performance is enabled by this unique device architecture that enables a high photoconductive gain of ≈10(4) with a response time of several milliseconds.

Data describing the insertion of sulphur dioxide into the carbon - tin bond of a range of substituted phenyltrimethyltin compounds in methanol and benzene solvents have been reconsidered. The reaction in methanol is cleanly second order, but the reaction in benzene has both a second-order and third-order component, the latter ascribable to an initial equilibrium formation of a SO2 complex with the phenyl ring followed by the insertion of a second SO2 molecule into the carbon-tin bond. Molecular orbital calculations have identified the transition states (TS) and the favoured reaction pathways for the second-order and third-order reaction pathways in benzene. The effects of solvents on TS and enthalpies of reaction have also been examined. New insights into the types of TS involved in electrophilic substitution reactions are revealed. Copyright

Aims To review the transparency of reports of behavioral interventions for pathological gambling and other gambling-related disorders. Methods We used the Transparent Reporting of Evaluations with Nonrandomized Designs (TREND) Statement to develop the 59-question Adapted TREND Questionnaire (ATQ). Each ATQ question corresponds to a transparency guideline and asks how clearly a study reports its objectives, research design, analytical methods and conclusions. A subset of 23 ATQ questions is considered particularly important. We searched PubMed, PsychINFO and Web of Science to identify experimental evaluations published between 2000 and 2011 aiming to reduce problem gambling behaviors or decrease problems caused by gambling. Twenty-six English-language reports met the inclusion criteria and were reviewed by three abstractors using the ATQ. Results The average report adhered to 38.4 (65.1%) of the 59 ATQ transparency guidelines. Each of the 59 ATQ questions received positive responses from anaverageof 16.9(63.8%)of thereports.Thesubsetof 23particularlyrelevantquestionsreceivedanaverageof 15.3 (66.5%) positive responses. Thirty-two of 59 (54%) ATQ questions were answered positively by 75% or more of the study reports, while 12 (20.3%) received positive responses by 25% or fewer. Publication year did not affect these findings. Conclusions Gambling intervention reports need to improve their transparency by adhering to currently neglected and particularly relevant guidelines. Among them are recommendations for comparing study participants who are lost to follow-up and those who are retained, comparing study participants with the target population, describing methods used to minimize potential bias due to group assignment, and reporting adverse events or unintended effects.

Caves provide excellent settings to examine evolutionary questions. Subterranean environments are characterized by similar and consistent conditions. Cave-adapted species often share characteristics such as diminished pigmentation, elongated limbs and reduced or absent eyes. Relatively little is known about the evolution and development of troglomorphic traits in invertebrates. In this study, we compare expression of the eye development genes hedgehog, pax6, sine oculis and dachshund in individuals from multiple independently derived cave populations of the amphipod Gammarus minus. hedgehog expression was significantly reduced in cave populations, compared to genetically related surface populations. Interestingly, no differences were found in pax6, sine oculis or dachshund expression. Because hedgehog-related genes are also involved in eye reduced in Astyanax mexicanus, these genes may be consistent targets of evolution during cave adaptation. These results provide support for the hypothesis of genomic ‘hotspots’ of evolution and allow comparison of adaptive mechanisms among diverse animals in subterranean environments.

The use of pulmonary artery catheterization (PAC) has declined secondary to associated complications and lack of demonstrable efficacy in the inpatient setting. Few studies have been published on the use of PAC in nonacute heart failure (HF) patients. The purpose of this study was to review the use of PAC in guiding advanced therapy in nonacute ambulatory HF patients. A retrospective observational study assessing our group’s practice pattern with regard to the use of PAC in 515 ambulatory HF patients, outcomes, and adverse events that resulted from its use was performed. A total of 159 ambulatory HF patients were referred for PAC; 7% underwent heart transplant, 6% had ventricular assist device (VAD) placement, 18% underwent inotropic therapy, and 48% had addition of therapy while 14% had subtraction of therapy. Adverse events occurred in 4% of ambulatory PAC. Patients who underwent heart transplant, VAD, or inotropic therapy had significantly elevated pulmonary capillary wedge pressures, mean pulmonary artery pressures, and depressed cardiac index. Patients selected for inotropic therapy also had significantly elevated right atrial pressures and depressed ejection fractions. PAC use safely guided medical therapy in more than half of the nonacute ambulatory patients. ©2011 Wiley Periodicals, Inc.

Background: Trans-scleral cyclophotocoagulation with diode laser has been well documented in the management of neovascular glaucoma. More recently, intravitreal bevacizumab has been increasingly employed to treat neovascular diseases of the eye. This study reports our initial experience with trans-scleral cyclophotocoagulation alone versus the combination of trans-scleral cyclophotocoagulation and intravitreal bevacizumab for management of neovascular glaucoma. Design: Retrospective uncontrolled comparative case series Participants: A total of 31 eyes of 30 consecutive patients were included - 11 eyes in the trans-scleral cyclophotocoagulation alone group and 20 in the combination trans-scleral cyclophotocoagulation and intravitreal bevacizumab group. Methods: The records of all patients diagnosed with neovascular glaucoma undergoing trans-scleral cyclophotocoagulation with or without intravitreal bevacizumab performed by a single ophthalmic surgeon in a glaucoma specialist centre were reviewed. Main Outcome Measures: Data collected included intraocular pressure, anterior segment neovascularisation, best-corrected visual acuity, use of medications and complications. Results: Mean reduction in intraocular pressure was 33.5mmHg in the trans-scleral cyclophotocoagulation group and 23.7mmHg in the combination group, a difference of 9.8mmHg (95% CI -1.5, 21.1). Complications included hypotony in three (27%) eyes in the trans-scleral cyclophotocoagulation group and two (10%) eyes in the combination group. Three eyes required evisceration. Conclusions: Trans-scleral cyclophotocoagulation alone is effective in lowering intraocular pressure in neovascular glaucoma. In this study, the addition of intravitreal bevacizumab to trans-scleral cyclophotocoagulation did not statistically advantage treatment outcomes. © 2010 The Authors. Clinical and Experimental Ophthalmology

Objectives. Radiotherapy to head and neck tumors can potentially damage the auditory pathways. This has relevance in cochlear implants and there is a need for clinical studies to confirm the feasibility of cochlear implantation in these patients. Methods. The records of all patients who had received cochlear implants at our institution were reviewed in this retrospective study and those who had prior irradiation for head and neck tumors were further studied. Case controls consisted of comparable cochlear implant recipients who did not have prior radiotherapy. Results. Four of 230 patients met the criteria for further study. They had received radiotherapy for nasopharyngeal carcinoma 11 to 28 years ago and the postimplant follow-up period ranged from 9 to 46 months. The implanted ear of each patient had favorable preoperative promontory stimulation results. Postimplant, all patients were satisfied with their hearing outcomes and the improvement in speech discrimination scores was comparable to the controls. These cases also illustrated specific clinical concerns, including 1) radiation-induced endocrine dysfunction was common and, if overlooked, could result in increased anesthetic risks, and 2) irreversible eustachian tube dysfunction led to chronic middle ear problems, which complicated surgery; the use of modified surgical techniques overcame these difficulties. Conclusions. Deafened postirradiated patients with nasopharyngeal carcinoma were able to achieve good postimplant hearing outcomes comparable to those of nonirradiated patients. Should cochlear implantation be indicated in patients who have had prior radiation to the head and neck, specific preoperative, intraoperative, and postoperative issues have to be addressed.

This study considers a time-series model with random coefficients in cointegration. The estimation problem can be solved by maximizing the log-likelihood. Asymptotic distributions of the least squares and maximum likelihood estimates are considered. The randomness of the cointegration vector is checked by a score-based test approach. The test statistic converges asymptotically to a functional of Brownian processes. An empirical application to two cointegrated series, federal fund rate and 90-day treasury bill rate is considered. Copyright 2004 Blackwell Publishing Ltd.

Effects of i.c.v. administration of 5,7-dihydroxytryptamine (5,7-DHT) on biochemistry and behavior were studied in awake Sprague-Dawley rats. It was found that 5,7-DHT depletion of striatal tissue levels of serotonin (5-HT) does not diminish extracellular levels until substantial depletions occur. This finding is similar to those observed after 6-hydroxydopamine lesions of the brain dopamine systems. Although varying amounts of 5,7-DHT produced serotonin depletions in striatal tissue, decreases in extracellular levels were only observed at tissue depletions greater than 60% compared to saline-injected control subjects. Thus, the effects of serotonin lesions which produce only moderate depletions may not be the result of decreased extracellular serotonin, but instead may be the result of compensatory changes in remaining neurons which maintain normal extracellular serotonin concentrations. Different degrees of striatal serotonin depletion were associated with opposite behavioral effects. Moderate levels of serotonin depletion (50-75%) produced evidence of increased anxiety, while these effects were no longer seen in rats with more severe 5-HT depletions (.75%).

NMR results indicate that, in the reaction between polyacrylamide and formaldehyde, crosslinking is due to methylenebisamide formation both intermolecularly and intramolecularly at low pH; at high pH, there is no evidence for crosslinking

Purpose: Selecting good beam orientations is an important step in the IMRT planning process that is usually completed by the planner based on their experience. In this study, we proposed a method for determining the minimum number of beams needed and the beam orientation for IMRT plans. Materials and Methods: The beam angle selection begins with a search of the best “one‐beam” plan. For this purpose, 36 single‐beam plans with the beam gantry angle from 0° to 350° every 10° degrees were optimized using Prowess Panther TPS. The two beam orientations with lowest dose to OARs and satisfying the plan constraints are selected. The next step, which applies for the remainder of selected beam orientations applies a different criterion ‐ a beam orientation is selected if it maximizes the conformality index while keeping the OARs does within tolerance. For example, for the third beam orientation, thirty‐four “three beam” plans in which two fixed beams are from previous step and third beam's gantry varying from 0° to 350° and not at the same beam angles previously selected was optimized. This step was repeated for next beam until the plan achieved a reasonable conformity. Results: It takes about 2h to running beam angle optimization. For the selected brain case, it has been shown that our selected 5 beam plan results in a better target conformity, 0.81 compared to 0.76, with similar OARs doses compared to 7 equispaced beam plans. Both of these plans satisfy dose constraints for OARs. Conclusions: We concluded that using fewer, well placed beams than equispaced beam has capacity of achieving as good plans in term of conformity and dose to OARs. This will enable a fully automatic IMRT planning process without going through a time consuming trial and error beam selection process.

Legalized gambling is more available and accessible than at any other time in American history. The public health impact of pathological gambling is just now beginning to be understood, as are the ...

Cellular immunity was studied in 73 patients with recurrent vaginal moniliasis and 37 healthy controls, by skin testing with the multitest CMI kit and Candida antigen, with measurement of lymphoblastic transformation to phytohemagglutinin, antigens of Candida albicans, mumps, and streptokinase. Eighteen patients (24.7%) had a hypoergic or anergic response to Candida antigen on skin testing versus two controls (5.4%), p = 0.01. Overall, the patient's lymphoblastic proliferation to mitogen and various antigens was not significantly different from that of the controls. However, a subgroup of younger women (19 to 29 years old) had impaired responses to Candida antigen when compared with age-matched controls, 58% versus 17%, p < 0.005. Most women with recurrent vaginal moniliasis had normal cellular immunity. (AM J OasTET GVNECOL 1992;166:887-90.)

The impact fracture toughness of plasticized cellulose acetate has been determined by linear elastic fracture mechanics over the temperature range 20–70°C. A major peak in fracture toughness at −10°C has been found to correspond to a secondary loss transition in the dynamic mechanical loss spectrum of plasticized cellulose acetate. At −10°C, the fracture toughness is directly proportional to the log of the maximum strain rate.

The developmental patterns of ABO saline isoagglutinins were determined in 272 children between birth and 16 years of age. The frequency of saline isoagglutinins was significantly higher in group O-O maternal-cord pairs compared to group A-O paired sera. The anti-A and anti-B titers increased gradually from 3 to 12 months: 30 per cent of group O and B children attained adult median titers of isoagglutinin, whereas only 4 per cent of group A children acquired adult anti-B titers. This slow development of anti-B in group A children persisted through the second year. Maternal isoagglutinins may exert a suppressive influence on the development of specific isoagglutinins in the first year of life.

A reinvestigation of the mechanism of formation of the [M – 1]+ ion in a series of N,N-dialkylbenzamides suggests that previous mechanisms put forward to account for the formation of the [M – 1]+ ion are deficient. A new mechanism is proposed which accounts for the data observed previously, as well as our results for a series of N,N-dialkyl-2-chlorobenzamides, 4-substituted N,N-dimethylbenzamides and some related compounds. For the N,N-dialkyl-2-chlorobenzamides, comparison of the abundances of the [M – 1]+ ion with the [M – 35]+ ion suggests that a concurrent reaction is occurring, besides loss of the ortho aromatic hydrogen atom. A study of substituent effects on the intensity ratio [M – 1]+/[M]+ shows an upward concave plot of this against σ+, suggesting that two competing mechanisms occur for the formation of the [M – 1]+ ion.

The fracture behaviour of gun propellant grains during impact has been measured on a modified Hopkinson Bar which uses a projectile as the input bar. Evidence for the detection of initial minor crack formation in seven-perforated cylindrical specimens of single base, double base and triple base propellant is presented. Under compressive load (pressurization rates of 100 GPa/s-200 GPa/s), minor crack formation does not immediately result in large scale crack propagation or fragmentation of the specimens. The single base and triple base propellant are equally more resistant to crack initiation than the double base propellant when tested in either the end-on or side-on modes. Implications for munition survivability are discussed in terms of mechanical frictional effects caused during compressive loading of cracked propellant or compressive heating in propellant cracks during the ballistic cycle.

Prenatal, intrapartum and postnatal factors are compared between 15 preterm infants, known to have periventricular leukomalacia (PVL) on ultrasound and 15 infants of similar birthweight and gestation who ultrasonographically showed no evidence of cystic lesions, and who are known to be neurologically normal at follow up. Prenatally, the incidence of antepartum haemorrhage was significantly higher in the PVL group. Intrapartum factors were similar between the two groups but postnatally, the PVL group had significantly lower PaCO2 readings during the first 72 h of life. It is postulated that a severe maternal bleed in late pregnancy and neonatal hypocarbia could significantly decrease cerebral perfusion and cause areas of ischaemia and infarction resulting in periventricular leukomalacia.

The National Magnetic Fusion Energy Computer Center (NMFECC) at the Lawrence Livermore National Laboratory (LLNL) has implemented a simple, yet powerful interactive operating system, the Cray Time-Sharing System (CTSS), on a Cray-1 supercomputer. CTSS augments the multi-programming batch facilities normally found in supercomputer systems with many of the interactive services typical of interactive minicomputer systems. This paper gives some of the historical background leading to CTSS and gives an overview of the system that emphasizes the strong points or unusual features such as multiple channels, decentralized control of resources, priorities and program scheduling, system recovery, and on-line documentation.

The depth of penetration of five urea-based deterrents and of dinitrotoluene into an extruded monoperforated nitrocellulose propellant has been studied. The depth of penetration is directly proportional to the concentration of the deterrent solution. Structural variation of the urea-based deterrents and increasing the water content of the alcoholic deterrent solutions have significant effects on the depth of deterrent penetration. Dinitrotoluene penetrates more rapidly than the urea deterrents in all solvents studied. The results are consistent with a diffusion with interaction mechanism. It is suggested that some previous evidence for such a mechanism was not definitive.

The hydrogen belts of membranes are defined as the regions consisting of hydrogen bond acceptors, i.e., the C=O groups of glycero- and sphingolipids, and hydrogen bond donors, i.e., cholesterol-OH, sphingolipid-OH, proteins, and water. Lipid-lipid hydrogen bonding in these belts has been suggested. The connection of such hypothetical bonding with the condensation effect, i.e., the apparent reduction of surface area occupied by phospholipids in mixed monolayers with cholesterol, has been tested with lipids possissing and lacking C=O groups: diester, diether, and dialkyl phosphatidylcholine, and analogous polyoxyethylene diglycerides. Condensation by cholesterol was observed for all lipids. Consequently, the hypothetical lipid-C=O-cholesterol hydrogen bonding is not a prerequisite for the condensation effect.

The birth prevalence of congenital rubella syndrome (CRS) in Western Australia has been around 20 per 10 000 live births with peaks up to 100 per 10 000 in rubella epidemic years. The rate appears to be falling but it is still too soon to know whether the rubella vaccination programme in Western Australia has made a significant impact. The cohorts of young women who would have received the schoolgirl vaccination programme are only now entering the child bearing age groups. Observed falls may be due also to delayed diagnosis particularly of cases of deafness only. The proportion of nonimmune young women who would have been eligible for the programme in one maternity hospital has fallen. This study needs to be repeated to ascertain whether further epidemics of rubella have resulted in peaks of CRS or whether the vaccination programme has started to have an effect.

Evidence for the existence of an interphasic region in the nitroglycerin-nitrocellulose matrix immediately surrounding the crystalline nitroguanidine filler in triple base propellant is presented for the first time. This interphasic region displays anomalous thermal expansion and mechanical relaxation behaviour compared to the bulk nitroglycerin-nitrocellulose matrix in the propellant. The interphasic region accounts for the highly unusual thermal expansion behaviour of triple base propellants containing long needlelike nitroguanidine crystals. An interphasic region does not occur in similar propellant when the nitroguanidine filler is replaced by crystalline RDX. Thus the interphase region is thought to be a manifestation of a significant bindernitroguanidine interaction. Implications for munition survivability stemming from the existence of a separate polymeric interphase are discussed in terms of the thermal and relaxation behaviour of the interphasic binder-crystalline filler interface.

Rate constants (k2W or k2A) for proton exchange between a phenol, its conjugate base, and a water or t-butyl alcohol molecule have been measured in a t-butyl alcohol-water mixture by nuclear magnetic resonance. Since k2W and k2A are both high (k2W > 108 sec−1 M−1), the ratio k2W/k2A measures the selective solvation of the O−-site (of the phenoxide ions) by water and t-butyl alcohol. In 11.47 mole % t-butyl alcohol — 88.53 mole % water, k2W/k2A is found to be 14 ± 3 when the ionic reactant is ortho-bromophenoxide ion, and 32 ± 8 when it is meta-nitrophenoxide ion. The results suggest that substituents have a marked effect on the selective solvation of the O−-site.

The 13C solvent induced chemical shifts (SICS) of the carbonyl carbon and the thermodynamic barriers to rotation about the CN bond of N,N-dimethylbenzamide are linearly related to the solvent parameter, ET(30). A multi-parametric solvent parameter approach indicates that the SICS are influenced equally by polar effects and hydrogen-bond donor effects. Rotational barriers for N,N-dimethylbenzamide may, in principle, be determined by measurement of the 13C chemical shift of the carbonyl carbon in a particular solvent.