cssi/SciSciGPT-SciSciNet huggingface dataset:
Large-scale three-dimensional phase field simulation of γ ′-rafting and creep deformation

Three-dimensional phase field simulations of coupled γ/γ ′ microstructural evolution and plastic deformation in single crystal Ni-Al are carried out at micrometer scales. Coherent γ/γ ′ microstructures and plastic deformation in γ-channels are described using a single, consistent methodology based on Khachaturyan's phase field microelasticity approach to coherent precipitates and dislocations. In particular, a new set of phase fields is introduced to characterize local density of dislocations from individual active slip systems. To increase the length scale of the phase field simulations, the Kim–Kim–Suzuki (KKS) treatment of γ/γ ′ interfaces was adopted. The rafting kinetics, precipitate-matrix inversion process and the corresponding creep deformation are characterized with respect to parameters such as applied stress and lattice misfit. The simulation results on γ ′-rafting kinetics and morphological evolution of the γ/γ ′ microstructures are compared with available experiment. The model can be used to ...
A continuous‐review inventory model with constant resupply time and defective items

As a result of imperfect production and inspection by suppliers, pilferage, and/or damage in transit, it is common that procurement orders may contain defective items. This article deals with a continuous-review inventory system with Poisson demand arrivals and constant resupply time. Items in resupply lots may not be of perfect quality. The operating characteristics of such a system are analyzed. For purposes of computational savings, an approximation scheme for the operating characteristics is presented. As a result of the approximation, the determination of the optimal ordering policy becomes much simpler. Extensive numerical tests suggest that the approximation scheme is very effective in giving the optimal or near-optimal ordering policies for such a system.
Molecular characterization of thymidine kinase mutants of human cells induced by densely ionizing radiation.

Abstract In order to characterize the nature of mutants induced by densely ionizing radiations at an autosomal locus, we have isolated a series of 99 thymidine kinase (tk) mutants of human TK6 lymphoblastoid cells irradiated with either fast neutrons or accelerated argon ions. Individual mutant clones were examined for alterations in their restriction fragment pattern after hybridization with a human cDNA probe for tk. A restriction fragment length polymorphism (RFLP) allowed identification of the active tk allele. Among the neutron-induced mutants, 34 52 exhibited loss of the previously active allele while 6 52 exhibited intragenic rearrangements. Among the argon-induced mutants 27 46 exhibited allele loss and 10 46 showed rearrangements within the tk locus. The remaining mutants had restriction patterns indistinguishable from the TK6 parent. Each of the mutant clones was further examined for structural alterations within the c-erbA1 locus which has been localized to chromosome 17q11-q22, at some unknown distance from the human tk locus at chromosome 17q21-q22. A substantial proportion (54%) of tk mutants induced by densely ionizing radiation showed loss of the c-erg locus on the homologous chromosome, suggesting that the mutations involve large-scale genetic changes.
Image Quality Considerations In Transform Coding

A review of adaptive image transform coding techniques is given. Adaptive techniques are superior to nonadaptive procedures; however, their implementation requires a significant degree of added complexity. A major aspect of adaptive transform coding is the understanding and utilization of the local statistical structure of the image. Rate adaptive communication and buffer feedback are also important aspects of adaptive coding procedures. The discussion emphasizes the image quality aspect of the coding process.
Excess pension asset reversions and corporate acquisition activity

Abstract This article examines the relationship between corporate acquisition activity and pension plan terminations that result in a reversion of surplus assets. We use a logit analysis to compare characteristics of terminating and nonterminating firms that held surpluses during the period 1980–1985. Our results indicate that reversions are more likely for firms that have larger pension surpluses, are less profitable, and are involved in acquisition activities. Pension reversions may have been used in corporate acquisition financing, as recent congressional investigations have inferred.
Professionalism in 21st century professional practice: autonomy and accountability in orthopaedic surgery.

Orthopaedic surgical practice is becoming increasingly complex. The rapid change in pace associated with new information and technologies, the physician-supplier relationship, the growing costs and growing gap between costs and reimbursements for orthopaedic surgical procedures, and the influences of advertising on the patient, challenge all involved in the delivery of orthopaedic care. This paper assesses the concepts of professionalism, autonomy, and accountability in the 21st century practice of orthopaedic surgery. These concepts are considered within the context of the complex value chain surrounding orthopaedic surgery and the changing forces influencing clinical decision making by the surgeon. A leading impetus for challenge to the autonomy of the orthopaedic surgeon has been cost. Mistrust and lack of understanding have characterized the physician-hospital relationship. Resource dependency has characterized the physician-supplier relationship. Accountability for the surgeon has increased. We suggest implant surgery involves shared decision making and “coproduction” between the orthopaedic surgeon and other stakeholders. The challenge for the profession is to redefine professionalism, accountability, and autonomy in the face of these changes and challenges.
Effects of heavy metals on water hyacinths (Eichhornia crassipes (Mart.) Solms)

Abstract Water hyacinths ( Eichhornia crassipes (Mart.) Solms) were exposed for 6 wk to solutions containing 0–5 mg/1 Ph, Cd or Cu. The metal concentrations and metal accumulations within plant tissues increased linearly with solution concentration in the order leaves
SU‐E‐I‐99: An Ultra‐High Resolution Small Field‐Of‐View Solid State X‐Ray Imaging Detector Based on an Electron Multiplying CCD

Purpose: To demonstrate the ultra‐high resolution capability of a small field‐of‐view (FOV) solid state x‐ray imaging detector based on an EMCCD sensor.Methods: A micro‐solid state x‐ray image intensifier (micro‐SSXII) was developed to serve as an ultra‐high resolution region‐of‐interest (ROI) imaging detector. It is based on an 8 micron, 1004 by 1002 pixel electron multiplying CCD (EMCCD) optically coupled to a 100 micron thick CsI(Tl) phosphor through a fiber optic window resulting in a FOV of 8 mm. The modulation transfer function(MTF) of the micro‐SSXII was measured by the slanted edge method. A cast of a rat kidney (made by mixing resin and iodine for contrast) and a mammography line pair test object were imaged at 50 kVp to demonstrate the detector's ultra‐high resolution capability visually. Results: The MTF was determined and was 5% at 20 cycles/mm. This is consistent with the clear visualization of the maximum 20 lp/mm group in the image of the mammography test object. Also, iodine bubbles with diameters as small as 25 microns, which are formed by the non‐uniform mixing of the iodine in the resin cast, can be clearly identified in the rat kidney vessels. Conclusions: The ultra‐high resolution capability (>20 lp/mm) but small FOV (8 mm) of the micro‐SSXII in combination with a low‐energy x‐ray source may have application for investigations of vascular specimen details and other fine structures where optical or other surfaceimagers would be unsuited for evaluating features below the surface. Contact radiography with this imager combined with a large higher‐load focal spot x‐ray tube may be a promising substitute for magnification radiography which is limited by the use of specialized low output microfocus x‐ray tubes and geometric un‐sharpness for large magnifications. Supported in part by: NIH Grants R01‐EB008425, R01‐EB002873 and an equipment grant from Toshiba Medical Systems Corp.
Modulation Transfer Function Of Anisoplanatic Optical Systems

Fourier analysis can be applied to an anisoplanatic optical system, if we define the modulation transfer function of such a system as the four-dimensional Fourier transform of its space-variant point spread function. We show that this approach can be used to estimate the band-width of the output image, and thereby provides a way of determin-ing the sampling rates required for computer simulation of such systems. We also show that the computer calculation of the image is less time-consuming to do in the spatial domain than in the frequency domain.© (1968) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Influence of lead on the glutathione status of Atlantic croaker tissues

The glutathione, cysteine and acid-soluble thiol status of Atlantic croaker (Micropogonias undulatus) tissues and the accumulation and subcellular distribution of lead were investigated after oral ingestion of lead chloride (equivalent to 1.2 mg Pb/100 g body weight/day) for up to 6 weeks. The glutathione contents of the liver and intestine increased to 1.4 × and 4.4 × control levels, respectively, after ingestion of lead for one week and did not increase further during chronic treatment. Significant increases in the glutathione contents of brain and kidney tissues were only observed after six weeks lead administration. These elevations in glutathione content accounted for most of the increases in acid-soluble thiol concentrations ob served in croaker tissues after lead treatment. The intestine accumulated the most lead (up to 50 μg/g), followed by the kidney (20 μg/g), liver (2 μg/g) and brain (< 1.0 μg), There was no apparent relationship between the accumulation of lead and glutathione content in these tissues above the threshold level of 1μg Pb/g tissue. Subcellular fractionation of hepatic tissue after injection with210Pb showed that nearly half of the lead was present in the cytosolic fraction which eluted on a Sephadex G-75 column in a peak with a molecular weight above 64,000, no210Pb was associated with glutathione or any other low molecular weight thiols. Incorporation of14C-glycine into hepatic glutathione, a measure of glutathione synthesis, was increased 1.8-fold in lead-exposed fish, whereas glutathione turnover was unaltered. These results suggest that the increase in glutathione content observed in lead-exposed fish is due to an increase in glutathione synthesis rather than a decrease in utilization of the tripeptide or to its sequestration by lead.
Formation of Hepatitis B Virus Covalently Closed Circular DNA: Removal of Genome-Linked Protein

Hepatitis B virus (HBV) contains a small, partially double-stranded, relaxed circular (RC) DNA genome. RC DNA needs to be converted to covalently closed circular (CCC) DNA, which serves as the template for all viral RNA transcription. As a first step toward understanding how CCC DNA is formed, we analyzed the viral and host factors that may be involved in CCC DNA formation, using transient and stable DNA transfections of HBV and the related avian hepadnavirus, duck hepatitis B virus (DHBV). Our results show that HBV CCC DNA formed in hepatoma cells was derived predominantly from RC DNA with a precise junction sequence. In contrast to that of DHBV, HBV CCC DNA formation in cultured cells was accompanied by the accumulation of a RC DNA species from which the covalently attached viral reverse transcriptase (RT) protein was removed (protein-free or PF-RC DNA). Furthermore, whereas envelope deficiency led to increased CCC DNA formation in DHBV, it resulted mainly in increased PF-RC, but not CCC, DNA in HBV, suggesting that the envelope protein(s) may negatively regulate a step in CCC DNA formation that precedes deproteination in both HBV and DHBV. Interestingly, PF-RC DNA, in contrast to RT-linked RC DNA, contained, almost exclusively, mature plus-strand DNA, suggesting that the RT protein was removed preferentially from mature RC DNA.
Brightness of Fine Detail in Ground Photography

For a number of typical outdoor photographic scenes on cloudless days, a statistical study has been made of logarithmic brightnesses and of differences of log brightnesses on adjacent pieces of fine detail, as they would be seen by a representative camera. Values were obtained photographically on Super XX film and also by means of a photoelectric telephotometer corrected to Super XX spectral response. The results do not disagree seriously with accepted values for the photographic brightness range. However the uncertainty in the meaning of “brightness range” is illustrated and a definition is proposed for a “99% range.” For difference of log brightness on fine detail, low values are found to predominate, with two-thirds of the differences below the average value of 0.15.
“Objectives-based” evaluation of strategic planning systems

Abstract A comparative study of more effective vs less effective planning systems is reported here, where effectiveness is treated in terms of the fulfillment of six key planning objectives. Based on data on the strategic planning systems and processes of over 200 North American companies, key systems design and contextual factors associated with effective planning are identified. It was found that dissatisfaction with formal strategic planning is not as widespread among practicing managers as is widely alleged. The degree of fulfillment of key planning objectives varies widely not only from company to company but also from objective to objective. Overall, the creativity and control orientation of the system and its level of functional integration were found to be the principal design factors contributing to the effectiveness of a strategic planning system.
Natural history and decision-making in patients with ventricular septal defect

Abstract The major determinant of the natural history of isolated ventricular septal defect is the size of the communication. In addition, the position of the VSD will affect the likelihood of diminishing size or spontaneous closure, the development of pulmonary outflow obstruction, and the possibility of prolapse of the aortic valve into the defect. Large ventricular septal defects cause congestive heart failure during infancy, and often require surgical repair in the first year of life. If pulmonary artery hypertension persists in unoperated infants, surgery is required within the first 2 years, even if symptoms have been controlled. Small ventricular septal defects with normal pulmonary artery pressure do not require surgical intervention, but some patients with pressure-restrictive ventricular septal defects who have large left-to-right shunts may be candidates for surgical closure if they are symptomatic. Patients with ventricular septal defect and high pulmonary vascular resistance (Eisenmenger's syndrome) are inoperable, but those with moderate elevation of pulmonary vascular resistance, and still a left-to-right shunt may benefit from surgical repair. Large subpulmonary VSDs with aortic valve prolapse require surgical closure. Questions remain regarding management of small subpulmonary defects in terms of the selection of patients and the timing of intervention.
LONG-TERM ANATOMICAL AND FUNCTIONAL OUTCOMES IN PATIENTS WITH DISORDERS OF SEXUAL DEVELOPMENT

Purpose To assess the long-term anatomical, and functional outcomes of adult patients who were surgically treated for DSD as infants or children. Material and Methods An attempt was made to contact patients 18 years or older, who were treated surgically for DSD as infants or children at our institution. Of 27 patients, we were able to reach only 13, and of these, 4 refused to participate in the extensive questionnaires. Patients were compensated $150.00 for completing the questionaires. Nine patients answered a detailed psychosocial questionnaire. Seven of the nine completed the female version of the Self Assessment of Genital Anatomy and Sexual Function Questionnaire. Five had CAH and 2 had MGD. Results The clitoris was judged too large in 4, small in 1, and not located in 2. In the 5 where location was possible, it was on the pubic bone in 1, just below the pubic bone in 1, at the top of the labia in 2, and below the top of the labia, just inside the vagina in 1. Six of the 7 patients noted the vaginal opening was adequate for sexual penetration, but three of the 6 indicated that penile penetration still caused tearing or bleeding. Five patients said their vaginal opening was in the anatomically correct position and 2 said it was far back near the anus. Three patients had strong, 3 had moderate, and 1 had no sexual pleasure with clitoral stimulation. Three had strong, 2 had mild, and 2 had no orgasms. Conclusions Long-term follow-up of adult DSD patients who had surgery as infants or children was disappointingly difficult to obtain. Of the small number of responders, most participated in sexual activities but functional results were mixed. It is important to develop better tracking systems for long-term follow up of adult DSD patients so that those who have residual functional problems can benefit from re-evaluation and further management.
Merging thesauri: principles and evaluation

An investigation is reported of ways to take advantage of the semantics in thesauri to improve: (1) indexing by providing descriptions of documents as sets of terms from the thesaurus; and (2) retrieval by assessing the relevance of documents to a query. Thesauri need to be updated to account for the evolution of the field they cover. Accordingly, various augmentation algorithms and methods to assess the usefulness of these augmentations are being studied. The augmentations consist of merging two existing thesauri. By keeping a consistent level of complexity among the structure manipulated by the merging algorithm, the reasoning method, and the evaluation procedure, an improvement of the performance of the merged thesaurus on both document indexing and retrieval is demonstrated. >
The modality shift experiment in adults and children with high functioning autism.

This study used the modality shift experiment, a relatively simple reaction time measure to visual and auditory stimuli, to examine attentional shifting within and across modalities in 33 children and 42 adults with high-functioning autism as compared to matched numbers of age- and ability-matched typical controls. An exaggerated “modality shift effect” relative to the TD children occurred for the children with autism in conditions involving the reaction time when shifting from sound to light but not from light to sound. No exaggerated MSE was found for the adults with autism; rather, their responses were characterized by a generalized slowness relative to the adults with TD. These results suggest a lag in maturational development in autism in basic information processing mechanisms.
Modern vitiligo genetics sheds new light on an ancient disease

Vitiligo is a complex disorder in which autoimmune destruction of melanocytes results in white patches of skin and overlying hair. Over the past several years, extensive genetic studies have outlined a biological framework of vitiligo pathobiology that underscores its relationship to other autoimmune diseases. This biological framework offers insight into both vitiligo pathogenesis and perhaps avenues towards more effective approaches to treatment and even disease prevention.
Statewide evaluation of a tobacco cessation curriculum for pharmacy students.

Abstract Background Previous studies suggest that healthcare professionals are inadequately trained to treat tobacco use and dependence. Because even brief interventions from clinicians improve patient quit rates, widespread implementation of effective tobacco cessation training programs for health professional students is needed. Methods Pharmacy students received 7–8 h of comprehensive tobacco cessation training. Participants completed pre- and post-program surveys assessing perceived overall abilities for cessation counseling, skills for key facets of cessation counseling (Ask, Advise, Assess, Assist, Arrange), and self-efficacy for counseling. Results A total of 493 students (82.3%) completed linkable pre- and post-training evaluations. Self-reported abilities, measured on a five-point scale, increased significantly from 1.89 ± 0.89 to 3.53 ± 0.72 ( P Conclusions Comprehensive training significantly improved pharmacy students' perceived confidence and ability to provide tobacco cessation counseling. The curriculum is applicable to other health professional training programs and currently is being used to train pharmacy, medical, nursing, and dental students.
Sexually dimorphic neuron number in lumbosacral dorsal root ganglia of the rat: Development and steroid regulation

Rats possess a sexually dimorphic neuromuscular system that controls penile reflexes critical for copulation. This system includes two motor nuclei in the lumbar cord and their target musculature in the perineum. The spinal nucleus of the bulbocavernosus (SNB) and the dorsolateral nucleus (DLN) motoneuron populations and their target perineal muscles are much larger in males than in females. The sex difference in motoneuron number develops via androgen-regulated differential cell death during the perinatal period; androgen also regulates retention of the target muscles. The developmental pattern and steroid sensitivity of peripheral afferents to the SNB/DLN motor nuclei were previously unknown. In order to characterize the peripheral sensory component of the dimorphic SNB/DLN system, the neurons of the relevant dorsal root ganglia (DRGs) were quantified in terms of number, size, and androgen sensitivity at various perinatal ages. DRG neuron number is greatest prenatally, then decreases in both sexes after birth; the timing and pattern of neuron number development are similar to those seen in the SNB and DLN. Postnatally, males have more DRG neurons than females, as a result of greater neuron death in the DRGs of females. Females treated with testosterone propionate during the perinatal period exhibit masculine development of DRG neuron number. Thus, the normal development of DRG neuron number parallels that of the SNB/DLN motor nuclei and target muscles in pattern and timing, is sexually dimorphic, and is regulated by androgen. © 1993 John Wiley & Sons, Inc.
A Study of the Relationship Between Self-Care, Compassion Satisfaction, Compassion Fatigue, and Burnout Among Hospice Professionals

Hospice care professionals (HCPs) experience a large number of stressors in their work settings. The purpose of this study was to investigate the relationship between self-care, compassion fatigue, burnout, and compassion satisfaction among HCPs. Thirty-seven HCPs were surveyed regarding their levels of compassion satisfaction, compassion fatigue, and burnout. Respondents also reported the types of self-care activities in which they took part. Results indicated a relationship between self-care strategies and lower levels of burnout and compassion fatigue, and higher levels of compassion satisfaction. Several suggestions are offered for continued research and practice in the hospice care field.
Coarsening by compatible relaxation

A proper coarse variable set for algebraic multigrid (AMG) solvers can be constructed using compatible relaxation (CR). For a given coarse set, CR is a modified relaxation scheme that keeps the values of the coarse variables intact. Its convergence factor is a predictor of the potential AMG efficiency, similarly to the smoothing factor in geometric multigrid. A practical, CR-based coarse set construction algorithm is presented. Numerical results for model problems are demonstrated. Copyright © 2004 John Wiley & Sons, Ltd.
Mortality study of beryllium industry workers occupational lung cancer

Abstract A cohort of 3685 white males employed during 1937–1948 in two major industries manufacturing beryllium was followed to the end of 1976 to evaluate lung cancer mortality experience. Lung cancer mortality among beryllium-exposed workers was contrasted with that of workers employed in the viscose rayon industry. Study results demonstrated that lung cancer mortality among beryllium-exposed workers was significantly greater than that expected on the basis of lung cancer mortality experience of workers in the viscose rayon industry having similar employment patterns. The results of the present study are consistent with earlier animal bioassay studies and recent epidemiologic studies indicating that beryllium is carcinogenic. The results of the present study are not consistent with speculation attributing the excessive lung cancer mortality among beryllium-exposed workers to personal characteristics of individuals having unstable employment patterns.
Geographical aspects of environmental pollution in India

Abstract Generally, most people are under the impression that environmental pollution is serious only in highly developed countries. The environmental problems of less developed countries result from poverty, population growth as well as urban-industrial development. In this paper India is taken as an illustration to discuss the types of pollution problems found in the less developed world.
LOR-OSEM: statistical PET reconstruction from raw line-of-response histograms

Iterative statistical reconstruction methods are becoming the standard in positron emission tomography (PET). Conventional maximum-likelihood expectation-maximization (MLEM) and ordered-subsets (OSEM) algorithms act on data which have been pre-processed into corrected, evenly-spaced histograms; however, such pre-processing corrupts the Poisson statistics. Recent advances have incorporated attenuation, scatter and randoms compensation into the iterative reconstruction. The objective of this work was to incorporate the remaining pre-processing steps, including arc correction, to reconstruct directly from raw unevenly-spaced line-of-response (LOR) histograms. This exactly preserves Poisson statistics and full spatial information in a manner closely related to listmode ML, making full use of the ML statistical model. The LOR-OSEM algorithm was implemented using a rotation-based projector which maps directly to the unevenly-spaced LOR grid. Simulation and phantom experiments were performed to characterize resolution, contrast and noise properties for 2D PET. LOR-OSEM provided a beneficial noise-resolution tradeoff, outperforming AW-OSEM by about the same margin that AW-OSEM outperformed pre-corrected OSEM. The relationship between LOR-ML and listmode ML algorithms was explored, and implementation differences are discussed. LOR-OSEM is a viable alternative to AW-OSEM for histogram-based reconstruction with improved spatial resolution and noise properties.
Paleoindian large mammal hunters on the plains of North America

From approximately 11,200 to 8,000 years ago, the Great Plains of North America were populated by small Paleoindian hunting groups with well developed weaponry and the expertise to successfully hunt large mammals, especially mammoths and bison. Mammoths became extinct on the Plains by 11,000 years ago, and, although paleoecological conditions were worsening, their demise may have been hastened by human predation. After this, the main target of the Plains Paleoindian hunters consisted of subspecies of bison, Bison antiquus and Bison occidentalis. As bison populations gradually diminished, apparently because of worsening ecological conditions, by approximately 8,000 years ago, human subsistence was forced into a greater dependence on small animal and plant foods. Human paleoecology studies of the Paleoindian time period rely heavily on multidisciplinary efforts. Geomorphologists, botanists, soil scientists, palynologists, biologists, and other specialists aid archaeologists in data recovery and analysis, although, with few exceptions, their contributions are derived from the fringes rather than the mainstream of their disciplines.
COGNITIVE PROCESSES IN PANIC DISORDER: AN EXTENSION OF CURRENT MODELS

Beck and Clark's 1997 information processing model of panic was presented and evaluated. In general, studies using the Stroop task have shown panic patients have a cognitive bias toward negative and personally relevant information. Several studies have also shown that panic patients tend to have more catastrophic thoughts and are more likely to misinterpret bodily sensations. Further, cognitive-behavioral therapy is more effective than drug therapies. The limitations of the cognitive model and cognitive-behavioral therapy were discussed, and an extension of current models was proposed. The extension of current models combines cognitive-behavioral and psychodynamic concepts and techniques and suggests that exposure in vivo used for agoraphobic situations and interoceptive exposure used for panic should also be applied to the underlying themes of panic disorder.
Discovery and design of DNA and RNA ligase inhibitors in infectious microorganisms.

Background: Members of the nucleotidyltransferase superfamily known as DNA and RNA ligases carry out the enzymatic process of polynucleotide ligation. These guardians of genomic integrity share a three-step ligation mechanism, as well as common core structural elements. Both DNA and RNA ligases have experienced a surge of recent interest as chemotherapeutic targets for the treatment of a range of diseases, including bacterial infection, cancer and the diseases caused by the protozoan parasites known as trypanosomes. Objective: In this review, we will focus on efforts targeting pathogenic microorganisms; specifically, bacterial NAD+-dependent DNA ligases, which are promising broad-spectrum antibiotic targets, and ATP-dependent RNA-editing ligases from Trypanosoma brucei, the species responsible for the devastating neurodegenerative disease, African sleeping sickness. Conclusion: High-quality crystal structures of both NAD+-dependent DNA ligase and the T. brucei RNA-editing ligase have facilitated the devel...
Domain 1.1 of the sigma(70) subunit of Escherichia coli RNA polymerase modulates the formation of stable polymerase/promoter complexes.

The sigma 70 (sigma(70)) subunit of Escherichia coli RNA polymerase specifies transcription from promoters that are responsible for basal gene expression during vegetative growth. When sigma(70) is present within polymerase holoenzyme, two of its domains, 2.4 and 4.2, interact with sequences within the -10 and -35 regions, respectively, of promoter DNA. However, in free sigma(70), DNA binding is prevented by domain 1.1, the N-terminal domain of the protein. Previous work has demonstrated that the presence of domain 1.1 is required for efficient transcription initiation at the lambda promoter P(R). To investigate whether this is a general property of domain 1.1, we have used five promoters to compare polymerases with and without domain 1.1 in in vitro transcription assays, and in assays assessing the formation and decay of stable, pretranscription complexes. We find that the absence of domain 1.1 does not render the polymerase defective at all of these promoters. Depending on the promoter, the absence of domain 1.1 can promote or inhibit transcription initiation by affecting the formation of stable pretranscription complexes. However, domain 1.1 does not affect the stability of these complexes once they are formed. For polymerases containing domain 1.1, the efficiency of stable complex formation correlates with how well the -10 and -35 regions of a promoter match the ideal sigma(70) recognition sequences. However, when domain 1.1 is absent, having this match becomes less important in determining how efficiently stable complexes are made. We suggest that domain 1.1 influences initiation by constraining polymerase to assess a promoter primarily by the fitness of its -10 and -35 regions to the canonical sequences.
Thrombosis in patients with paroxysmal noctural hemoglobinuria is associated with markedly elevated plasma levels of leukocyte-derived tissue factor

Thromboembolism is a frequent complication of paroxysmal nocturnal hemoglobinuria (PNH) and contributes significantly to patient morbidity and mortality. A number of mechanisms have been proposed to explain the increased incidence of this complication of PNH. Increased platelet activation with platelet microparticle formation and depression of cell surface-mediated fibrinolysis has been demonstrated in patients with PNH. We have studied two patients with hemolytic PNH who had recurrent and refractory venous thromboembolic events despite therapeutic anticoagulation. Plasma samples from both patients demonstrated marked hemostatic activation as determined by elevated plasma thrombin-antithrombin complexes (TAT) and D-dimers. Plasma samples from both patients were also shown to contain markedly elevated levels of circulating tissue factor (TF), which was shown to be predominantly derived from monocytes and macrophages. In one patient, a successful allogeneic bone marrow transplant resulted in a reduction in hemostatic activation associated with a marked decrease in circulating tissue factor to near normal levels. We propose that thrombosis in PNH results from increased tissue factor expression by complement injured CD55- and CD59-deficient monocytes and macrophages.
MRI-based temperature and SAR mapping with a new dual-coil solenoid/birdcage heating/measurement system

We describe an MRI-based method for mapping temperature and specific absorption rate (SAR) using a solenoid coil and a birdcage coil for heating and imaging of a weakly conductive dielectric sample, respectively. The accuracy and the quality of SAR/temperature mapping are enhanced by separating the heating and imaging RF coils. 50 W of RF power is applied to the solenoid coil to heat the conductive agar-gel phantom for 120 sec. Maps of temperature increase were acquired with an MRI-based method. The MR-based measurements were in good agreement with fiber optic measurements. Finally, the dual-coil heating system was simulated using the finite difference time domain (FDTD) method. The distribution of numerically-calculated and experimentally-acquired SAR were also in good agreement.
Solid state stability of proteins III: Calorimetric (DSC) and spectroscopic (FTIR) characterization of thermal denaturation in freeze dried human growth hormone (hGH)

This research is a study of the changes in secondary structure (Fourier transform infrared spectroscopy, FTIR), aggregation, and loss of the magnitude of the heat of denaturation upon scanning to and partially through the temperature range of the thermal denaturation peak of a model protein, human growth hormone (hGH). We study two formulations, a system of essentially pure protein (with a trace of phosphate buffer) and a system formulated with trehalose in a 3:1 trehalose:hGH weight ratio. The extent of denaturation is measured by loss of secondary structure by FTIR, the loss of heat of denaturation by differential scanning calorimetry (DSC), and the fraction of protein aggregated by HPLC. We examine loss of structure on heating to the DSC onset of thermal denaturation and restoration of structure by cooling below the denaturation temperature and holding to (nominally) allow time for refolding, and we also examine restoration of structure upon dissolving and refreeze drying samples heated to selected temperatures in the denaturation range. We find that denaturation occurs only above the glass transition temperature, is highly cooperative, and is only reversible by redissolving the “denatured” formulated (trehalose) solid. Further, all measures of the extent of denaturation are in essential agreement. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:5122–5131, 2008
Study of low-salinity waterflooding for single- and two-phase experiments in Berea sandstone cores

Abstract Single-phase experiments were carried out in Berea sandstone to understand the behavior of the water–rock system and establish a baseline to interpret multiphase experiments. The water–rock reactions at microscopic level are reflected in the macroscopic scale by alteration in permeability in the rock and pH in the effluent. In our experiments we assume that the significant changes are solely a result of the alteration of the brine salinity since the composition of the brine and mineralogy of the core were held constant. Injection of brine with 1% salinity produced permanent permeability reduction due to fines release. Two-phase experiments were carried out on undamaged and damaged Berea sandstone cores. Comparison of single-phase and two-phase experiments results in undamaged Berea cores that showed the same pressure and pH behavior when low salinity waterflooding is performed. Incremental oil production was observed in both undamaged and damaged cores suggesting that the mechanism of incremental production during low salinity injection is not solely related to fines migration.
Free energy of nucleating droplets via cluster-integral series

A cluster-integral series is developed for the calculation of the droplet and crystallite partition functions involved in the classical theory of homogeneous nucleation. These formal series reduce the calculation of droplet free energies to the consideration of few-body integrals similar to those which determine the virial coefficients of an imperfect gas. Theories are proposed which correspond to infinite-order series resummations directly analogous to the Percus-Yevick and hypernetted-chain integral equations for simple liquids. The cluster-integral expansion coefficients through sixth order are evaluated for argon droplets over a wide range of temperatures by a very efficient specialized Monte Carlo sampling technique. These coefficients are used in two distinctly different ways: direct truncation of a suitable rearrangement of the series (star-tree approximation), and formation of Pad\'e approximants for a generating function identified as being well suited for this purpose. By comparing the results obtained from these different procedures, it is concluded that the predicted droplet free energies are quite accurate in the range of droplet size of special interest in homogeneous nucleation theory, i.e., the inaccuracy appears to be less than 3% in the free energy per particle for droplets of 80 argon atoms.
Contributions of dorsal root reflex and axonal reflex to formalin-induced inflammation

The dorsal root reflex (DRR) and the axonal reflex (AR) are antidromic activities in primary afferents and are involved in neurogenic inflammation. DRRs and/or ARs lead to release of neuropeptides calcitonin gene-related peptide (CGRP) and substance P (SP). CGRP causes blood vessels to dilate leading to an increase in blood perfusion, whereas SP causes plasma extravasation, leading to edema. Both DRR and AR can be evoked by noxious stimuli. The goal of this study was to determine the role of DRR and AR in neurogenic inflammation by examining the blood perfusion (BP) change in hindpaws in response to formalin injection (an acute inflammatory agent). Laser Doppler images were collected simultaneously in both hindpaws in anesthetized rats to determine the level of BP. Local lidocaine was applied to the left sciatic nerve to block both orthodromic signals and antidromic DRRs without affecting ARs. All rats then received a subcutaneous formalin injection to the left hindpaw. Our results showed that (1) the mean BP of the left paw increased significantly following formalin injection, with or without lidocaine; (2) application of lidocaine in the left sciatic nerve alone significantly increased BP ipsilaterally; (3) formalin injection following lidocaine application significantly increased BP more than the group without lidocaine; and (4) there was delayed significant BP increase in the right (contralateral) hindpaw following formalin injection with or without lidocaine. It is concluded that ARs play a more important role than DRRs in formalin-induced neurogenic inflammation.
The effects of ligation of the subclavian artery on the bones and soft tissues of the arms

Children whose subclavian artery was sacrificed for a Blalock-Taussig operation were noticed to have a smaller and often a shorter arm on the ligated side. Arms of 28 such patients were studied radiologically. It was found that interruption of the subclavian artery usually caused a diminution both in longitudinal growth of long bones and also in muscle thickness. Bone age and circumferential growth of long bones were not affected. Subcutaneous fat sometimes increased in thickness.
Sorption of oxygen and water by cobalt phthalocyanine

Abstract Organic semiconductors such as phthalocyanines have possible applications ranging from photovoltaic devices to fuel cell electrodes. Their properties are very sensitive to preparation and environment however. This sensitivity motivated this study of the effect of gas exposure on surface composition. The uptake of oxygen and water by a freshly deposited film of cobalt phthalocyanine (CoPc) was measured using Auger spectroscopy. Oxygen was irreversibly absorbed at room temperature to a saturation concentration of one oxygen molecule per CoPc in the sampled depth. The initial sticking probability of oxygen on CoPc is about 1 × 10 -4 but for oxygen pressures greater than 10 -5 Pa, the migration of the oxygen into the bulk limits the rate of oxygen uptake to 1 × 10 11 molecules/cm 2 s. Water vapor does not absorb at room temperature for partial pressures up to 10 -3 Pa except under the influence of an electron beam. In this case, the oxygen concentration reaches the same level as for oxygen exposure.
Enhanced proteolysis and changes in membrane-associated calpain following phenylhydrazine insult to human red cells☆☆☆

Phenylhydrazine-mediated protein damage in human red cells has been assessed using HPLC, one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and immunoblot analysis of major membrane proteins. The association of the Ca2+-activated neutral protease, calpain, with membrane proteins following hydrazine insult was also examined using immunoblot analysis. HPLC amino acid analysis of red cell suspensions was employed to quantify proteolysis. Phenylhydrazine (4 mm) increased the rate of leucine, lysine, and histidine release by ∼12-, 7-, and 5-fold, respectively. N-acetylcysteine (20 mm), dithiothreitol (50 mm), and dimethylthiourea (50 mm) decreased the rate of phenylhydrazine-stimulated amino acid release by ∼30–50%; in contrast, the free radical scavengers and antioxidants dimethylfuran (50 mm) and dimethyl sulfoxide (50 mm) were without significant effect. The calcium chelator, EGTA (10 mm), inhibited phenylhydrazine-stimulated proteolysis by ∼30%. Phenylhydrazine (4 mm) caused attenuation of the major membrane protein bands present in the SDS-PAGE pattern and extensive smearing of a band in the region of ∼28 kDa. Free radical scavengers and antioxidants failed to ameliorate significantly membrane protein damage in phenylhydrazine-treated cells as judged by SDS-PAGE. Immunoblot analysis of spectrin confirmed these results. Two-dimensional SDS-PAGE of membrane proteins following phenylhydrazine treatment, however, revealed the appearance of new protein spots and a loss of existing protein spots as compared to control. Western blot analysis of membrane-associated calpain (79 kDa (proenzyme), 77- and 75-kDa forms) was also performed. Phenylhydrazine-treated red blood cells exhibited concentration- and time-dependent changes in the level of membrane-associated procalpain relative to control. The inhibitors N-acetylcysteine, dithiothreitol, dimethylthiourea, and dimethyl sulfoxide in the presence of phenylhydrazine appeared to preserve the level of procalpain in association with the membrane proteins, but only N-acetylcysteine and dithiothreitol protected the 77- and 75-kDa forms. In contrast, dimethylfuran in the presence of phenylhydrazine caused a substantial decrease in all three forms of membrane-associated calpain. In phenylhydrazine-treated hemolysate, the level of the 77- and 75-kDa forms of membrane-associated calpain was decreased relative to control. These forms were absent when EGTA (10 mm) was included in the incubation and the level of proenzyme was decreased. These data suggest that calpain is recruited to the membrane following hydrazine insult, undergoes a Ca2+-dependent conversion to the active forms, and may be involved in the degradation of damaged cytosolic and membrane protein(s).
Mild intellectual deficits in a child with 49,XXXXY.

Abstract Severe mental retardation usually is present in males with a 49,XXXXY karyo-type, although occasionally, intellectual functioning has been reported to be in the mild range of mental retardation. One child was previously described to have normal development at 15 months, but had mental retardation at 41 months. We present a male with 49,XXXXY who had mild-cognitive and motor delays and age-appropriate adaptive skills at 59 months. Greatest deficits were in expressive verbalizations similar to other male sex chromosome abnormalities. Mosaicism could not be demonstrated in blood or skin specimens. Although most males with 49,XXXXY syndrome will have significant mental retardation, findings in our patient and other reports suggest that variability in intellectual functioning may occur, in some instances, and may justify guarded optimism in affected males demonstrating close to or age-appropriate developmental skills through early childhood.
Rates of energy transfer between tryptophans and hemes in hemoglobin, assuming that the heme is a planar oscillator.

Using the Forster equations we have estimated the rate of energy transfer from tryptophans to hemes in hemoglobin. Assuming an isotropic distribution of the transition moments of the heme in the plane of the porphyrin, we computed the orientation factors and the consequent transfer rates from the crystallographic coordinates of human oxy- and deoxy-hemoglobin. It appears that the orientation factors do not play a limiting role in regulating the energy transfer and that the rates are controlled almost exclusively by the intrasubunit separations between tryptophans and hemes. In intact hemoglobin tetramers the intrasubunit separations are such as to reduce lifetimes to 5 and 15 ps/ns of tryptophan lifetime. Lifetimes of several hundred picoseconds would be allowed by the intersubunit separations, but intersubunits transfer becomes important only when one heme per tetramer is absent or does not accept transfer. If more than one heme per tetramer is absent lifetimes of more than 1 ns would appear.
The geochemical behavior of refractory noble metals and lithophile trace elements in refractory inclusions in carbonaceous chondrites

Recent models of Ca, Al-rich (CAI) inclusion petrogenesis, and the recent availability of thermodynamic data have led to the reexamination of the geochemical behavior of the refractory noble metals (RNM) and several lithophile refractory trace elements in CAI's in the context of distillation models. Here, pertinent chemical and mineralogical properties of the various classes of refractory inclusions are reviewed, and calculations of the stability of LRTE-RNM alloys and several LRTE oxides under nebular conditions are presented. The calculations, observations and experimental results are applied to a new model of the origin of refractory metal nuggets, and a specific mechanism is identified for producing Group II chemical patterns in a cold star nebula by fractionating interstellar dust at low temperature on the basis of physical differences between different populations of pre-solar grains.