cssi/SciSciGPT-SciSciNet huggingface dataset:
Formation of massive sulfide deposits on oceanic ridge crests: Incremental reaction models for mixing between hydrothermal solutions and seawater

Equilibrium path calculations have been used to model mixing between hot (350°C) hydrothermal solutions and ambient seawater, in an attempt to simulate mineral precipitation at seafloor vents. These calculations predict temperatures of precipitation, paragenetic sequence of minerals, and chemical composition of chimney deposits associated with vents on the seafloor at 21°N, EPR. Assuming sulfate-sulfide disequilibrium during mixing, the paragenetic sequence revealed is: chalcopyrite, anhydrite, pyrrhotite, pyrite, sphalerite, graphite, and barite. When sulfate-sulfide equilibria is permitted during mixing, however, reduction of small amounts of sulfate results in early precipitation of pyrite and a sequence of Cu-rich sulfide minerals (chalcopyrite-bornite-chalcocite-covellite). This sequence is analogous to that observed in thin chimney walls. The calculations indicate that sulfide mineral precipitation occurs in response to both cooling and change in composition of the hydrothermal solutions as a result of mixing. Varying the amount of mixing with respect to temperature, simulating conductive heating of seawater prior to mixing, results in only minor variations in the sequence and abundance of precipitated phases. Anhydrite precipitation during mixing occurs early, which is consistent with formation of an anhydrite leading edge of chimney structures. Similarly, extrapolation of warm spring data from Galapagos to zero SO4 concentration suggests anhydrite formation due to mixing with seawater beneath the seafloor, most likely below the level of reactive calcareous sediments. Subsequent interaction of the mixed hydrothermal solution with those sediments results in elevated and variable Ca concentrations estimated for end-member solutions from the Galapagos. Precipitation of Mg hydroxide sulfate hydrate in the walls of the vent chimneys at 21°N, EPR, occurs as a result of conductive heating of ambient seawater with only very minor amounts of mixing. In contrast, precipitation of amorphous silica in the vents must be due to conductive cooling of the hydrothermal solutions. Thus, incremental reaction calculations demonstrate that reactions occurring in and associated with venting ridge crest hydrothermal solutions can be effectively modeled using the thermodynamic data and reaction modeling codes available today. Departures from equilibrium required to accurately model the mixing process are easily accommodated and consistent with data from the vents and vent forming materials.
The ν3 fundamental band of HCNH+ and the 2ν3 ← ν3 and ν2 + ν3 ← ν2 hot bands of HCO+

Abstract The ν 3 (CN stretch) fundamental band of HCNH + and the 2 ν 3 ← ν 3 , ν 2 + ν 3 ← ν 2 hot bands of HCO + have been observed in the 5-μm region using a tunable infrared diode laser and an ac glow discharge. We have combined these transitions with previously observed transitions and determined the following molecular constants: HCNH + , B e = 37 275,4(7) MHz and α 3 = 192.4(3) MHz; HCO + , χ 23 = 0.134(2) cm −1 and χ 33 = −10.054(2) cm −1 . We also calculated B e 's of HCNH + isotopic species by scaling α i from the theoretical prediction and estimated the equilibrium bond-length of HCNH + .
Individual odours and mate recognition in the prairie vole, Microtus ochrogaster

Abstract A habituation-discrimination technique was used to demonstrate that male and female prairie voles can discriminate individual differences in the odours of soiled shavings and urine from male and female conspecifics. A second experiment, employing a Y-maze, showed that females significantly preferred the odours of their mate over those of either another mated male or an unmated male. Males preferred their mate's odours to those of other mated females but showed no significant preference between the odours of their mate and those of a virgin female. A third experiment demonstrated that, over a 10-h period, females built nests and/or stayed preferentially on the side of a Y-maze containing their mate's odours. Likewise, males preferentially built nests in their mate's side compared to the side containing odours from a virgin female. However, although the same trend was present when mate odours were paired with odours from another mated female, the preference was not statistically significant. Taken as a whole, these results indicate that mate recognition may be an important of individually distinctive odours in this species.
Murine toxicology and pharmacokinetics of novel retinoic acid metabolism blocking agents

Novel potent C-4 azolyl retinoic acid metabolism blocking agents (RAMBAs)—VN/14-1, VN/50-1, VN/66-1, VN/67-1, and VN/69-1, have been synthesized and investigated for their in vitro and in vivo effects against breast and prostate cancers. These RAMBAs, in addition to being potent inhibitors of all-trans-retinoic acid (ATRA) metabolism have potent anti-cancer properties and in vivo anti-tumor efficacies as characterized in breast and prostate cancer models. Here we determined the toxicity and pharmacokinetics (PK) of these various RAMBAs. Preliminary acute toxicity studies of these RAMBAs were carried out using Swiss NIH mice. The toxicity profile of the RAMBAs was evaluated relative to ATRA. Three different doses (8.3, 33, and 100 μmol/kg/day) of ATRA and RAMBAs were administered on a daily basis subcutaneously for 14 days to the mice. Clinical signs of toxicity alopecia, scaly skin, and loss of body weight in the mice were observed during the study and the maximum tolerated dose was determined. PK of selected agents (VN/14-1, VN/50-1, and VN/66-1) was studied in Balb/C mice after a single dose subcutaneous administration. Plasma concentrations of the agents were quantitatively determined using a high-performance liquid chromatographic method with ultraviolet detection. Plasma concentration versus time profiles were fit to various PK structural models and relevant PK parameters were estimated. VN/66-1 and VN/69-1 were found to be the least toxic even at the highest doses when compared to the other RAMBAs and ATRA. VN/66-1 had the longest half-life, the slowest clearance, and the greatest exposure. Based on PK characteristics and toxicity studies, VN/66-1 appeared to be the most favorable agent. However, both VN/14-1 and VN/66-1 are our leads based on the fact that VN/14-1 has been found to be highly effective in endocrine-sensitive and -resistant breast cancer cells and tumors with little toxicity. Our findings provide valuable information that will be used to select RAMBAs and establish therapeutic regimens that provide optimal efficacy with minimal toxicity.
Developmental and Ethnic Issues Experienced by Emerging Adult African American Women Related to Developing a Mature Love Relationship

This qualitative study explored perspectives of emerging adult African American women on the development of mature love relationships. Inductive analysis of focus group interviews, conducted with a purposive sample of 31 African American women, yielded themes related to relationship goals and characteristics, and interpersonal and societal challenges to finding the right partner and developing a mature love relationship. Core categories that emerged from analysis of the discussions were (1) age and relationship goal differences within the emerging adult group, (2) mature love relationship goals and characteristics, (3) interpersonal obstacles to finding the right partner, and (4) societal obstacles to finding the right partner. Two approaches—black womanist/feminist thought (Collins, ; Walker, ) and relationship maturity theory (Paul & White, )—were then combined to explain the influence of historic and contemporary interpersonal and societal factors on developmental and ethnic issues that challenge posit...
Reactive hyperemic response of the brachial artery: Comparison of proximal and distal occlusion

Rationale and Objectives. The authors compared the postocclusion hyperemic responses of the brachial artery after occluding blood flow proximal to and distal to the studied area. Materials and Methods. Response of the brachial artery to hypoxia was evaluated with duplex Doppler ultrasound in 13 healthy subjects. A pneumatic tourniquet was first positioned 2–5 cm superior to the left elbow, proximal to the area of artery studied. Two hours later the response was remeasured with the tourniquet positioned 2–5 cm inferior to the elbow, distal to the artery studied. Arterial diameter, mean and peak flow velocities, and heart rate were assessed. Results. No significant differences were observed between measurements of baseline and postischemic arterial diameter, percentage diameter change, baseline mean arterial blood flow velocity, baseline peak arterial blood flow velocity, or postischemic heart rate obtained with proximal occlusion of the artery and those obtained with distal occlusion. In contrast, mean and peak postischemic arterial blood flow velocity and preocclusion heart rate were higher in measurements made during proximal artery occlusion. Significant correlation was found between measurements of percentage change in artery diameter obtained with proximal artery occlusion and those obtained with distal occlusion ( r = 0.611, P Conclusion. There are no major differences in postischemic changes in brachial artery diameter related to reactive hyperemia between blood flow occlusion applied proximal and distal to the studied area. However, there are significant differences in the mean and peak systolic velocities. Either occlusion site can be used for clinical studies if arterial diameter change is monitored, but if velocity measurements are being compared, a single occlusion site should be chosen.
Cyclic AMP in relation to proliferation of the Epidermal cell: a new view

Abstract Four agents known to increase the level of cellular cAMP by different means (cholera toxin, dibutyryl cAMP, methyl isobutyl xanthine and isoproterenol) increase the growth of colonies of cultured human epidermal cells and of keratinocytes derived from other stratified squamous epithelia. This effect is due to an increase in the overall rate of cell proliferation in the colonies. When added to cultures under hitherto optimum conditions for epidermal cell growth [in the presence of supporting 3T3 cells and epidermal growth factor (EGF)], most of the agents exert an effect of considerable magnitude, the toxin being the most potent. Since the toxin exerts an effect in the absence of supporting 3T3 cells, it must be able to act directly on the keratinocytes. It can also act in the absence of EGF and of medium conditioned by 3T3 cells, although proliferation is greatest when supporting 3T3 cells and EGF are present. The increased proliferation in the presence of the toxin is associated with an increased proportion of small cells known to include the multiplying fraction. The use of the toxin makes the cultivation of keratinocytes from epidermis and other stratified squamous epithelia much easier and prolongs the culture life of the cells. Whether cell proliferation in the intact epidermis is regulated through agents affecting cAMP (in a direction opposite to that suggested by much of the earlier literature) remains to be elucidated, but the existence of such a mechanism is cultured cells suggests that it may function in the intact epithelium.
The antigenic determinants of most of the proteins coded by the three serotypes of reovirus are highly conserved during evolution

Abstract The antigenic relationships of the proteins encoded by strains of the three reovirus serotypes were assessed by measuring the efficiency with which they were precipitated from infected cell extracts by antisera against the three serotypes. While the antigenic determinants on some proteins, particularly those on the minor outer capsid shell component σ-1, display type-specificity, the antigenic determinants on most cognate proteins encoded by the three serotypes are very similar. This is true even for the proteins of serotype 2, the genome of which is related to those of serotypes 1 and 3 by no more than 10% as judged by RNA-RNA hybridization. The results indicate that the antigenic determinants on most of the proteins of the three reovirus serotypes have been highly conserved during evolution.
Optimization of slider air bearing contours using the combined genetic algorithm-subregion approach

A hybrid optimization approach, the combined genetic algorithm-subregion method, which combines the advantage of the genetic algorithm and the subregion approach, is presented. Using a binary string to represent a selected design space, the combined genetic algorithm-subregion method adopts the genetic algorithm to perform the optimization process. Starting from a pico slider design originally flying at 14 nm, optimized designs were obtained for sliders with target flying heights of 7, 5 and 3.5 nm, respectively. The results show that the combined genetic algorithm-subregion method has good convergence with a substantial reduction of computation time.
High capacity anode materials for Li-ion batteries based on spinel metal oxides AMn2O4 (A = Co, Ni, and Zn)

Manganites of transition and/or post-transition metals, AMn2O4 (where A was Co, Ni or Zn), were synthesized by a simple and easily scalable co-precipitation route and were evaluated as anode materials for Li-ion batteries. The obtained powders were characterized by SEM, TEM, and XRD techniques. Battery cycling showed that ZnMn2O4 exhibited the best performance (discharge capacity, cycling, and rate capability) compared to the two other manganites and their corresponding simple oxides. Further studies on the effect of different sintering temperatures (from 400 to 1000 °C) on particle size were performed, and it is found that the size of the particles had a significant effect on the performance of the batteries. The optimum particle size for ZnMn2O4 is found to be 75–150 nm. In addition, the use of water-soluble and environmentally friendly binders, such as lithium and sodium salts of carboxymethlycellulose, greatly improved the performance of the batteries compared to the conventional binder, PVDF. Finally, ZnMn2O4 powder sintered at 800 °C (<150 nm) and the use of the in-house synthesized lithium salt of carboxymethlycellulose (LiCMC) binder gave the best battery performance: a capacity of 690 mA h g−1 (3450 mA h mL−1) at C/10, along with good rate capability and excellent capacity retention (88%).
Retroviral Vaccines: Challenges for the Developing World

The two major foci of HIV-1 infection in Asia Thailand and India have separate HIV-1 epidemics related to distinct HIV-subtypes. By the late 1980s or early 1990s there were two distinct HIV-1 epidemics in India. One epidemic particularly in Manipur region was typical of intravenous (IV) drug-associated epidemics and was likely due to subtype B. The other has the patterns of a typical sexually transmitted disease and was likely due to subtype C. The two epidemics in Thailand follow a similar delineation to those in India. Yet unlike India a new HIV-1 has emerged HIV-1 E in both epidemics. Subtypes C and E viruses from Asia are associated with efficient heterosexual transmission. These HIV-1 subtypes grow considerably better in Langerhans cells (highly prevalent in tissues of the vagina cervix and penis foreskin and almost absent from the rectum) than does HIV-1 subtype B. HIV-1 B viruses appear to have lost their affinity for efficient heterosexual transmission through mutation suggesting that HIV-1 B can be maintained in groups where transmission by vaginal sex is not needed (i.e. high density of contacts with homosexuals and/or IV drug users). A homogeneous heterosexual population with the highest incidence of new HIV-1 infections which is exposed to the same viral subtype or strain is the ideal test population for designing and testing an HIV-1 vaccine. The ideal HIV-1 test vaccine is the polymerized envelope antigen gp120. The safety of live attenuated HIV vaccines is doubtful. It appears that HIV-2infection provides some protection against HIV-1 infection (cross-reactivity immunity). In conclusion trials of HIV-1 vaccines are needed but should use HIV-1 C or E strains that spread rapidly by vaginal sex. These strains can be isolated from vaginal fluids with tropism for Langerhans cells.
Dynamic functional imaging of relative cerebral blood volume during rat forepaw stimulation

Dynamic measurements of regional changes in cerebral blood volume (CBV) were performed in rat models of hypercarbia and focal neuronal activation using T2-weighted imaging after injection of an intravascular contrast agent with a very long blood half-life. Calculated percent CBV change during hypercarbia was consistent with literature results from other non-invasive modalities. Equivalent percent CBV increases were found using spin- and gradient-echo images, suggesting proportional changes in blood volume for capillaries and small veins. During electrical stimulation of rat forepaw, focal CBV response to stimulation (24 ± 4%) was significantly delayed relative to blood oxygen level dependent (BOLD) signal after both onset and cessation of stimulation. Poststimulus CBV decay was temporally consistent with the BOLD poststimulus undershoot. The use of exogenous agent increased the functional contrast-to-noise ratio relative to BOLD imaging by 5.7 ± 1.3 at a magnetic field strength of 2 Tesla and 1.5 ± 0.2 at 4.7 Tesla.
Congestion of Point-to-Point Mobile Objects

Abstract Traffic congestion in point-to-point movement is studied using four simple traffic models. The four traffic models studied are movement between randomly chosen starting and destination points, back and forth movement between same two points, movement with preference of horizontal and vertical paths, and movement along shortest paths. The congestion properties of these traffic models are studied using computer simulation. It is found that the first and the third model has a sudden phase transition from free flow to jammed state at a critical system density, the second model has a gradual transition from free flow to jammed state, and the fourth model results in a simple deadlock. The phase transition properties and the critical densities are studied in detail. The emerging traffic jam patterns of the traffic models are also presented.
How many neurosurgeons does it take to write a research article? Authorship proliferation in neurosurgical research.

OBJECTIVE Authorship proliferation in biomedical research has become rampant; the proportion of single-author articles is decreasing, the percentage of multiauthor articles is increasing, and the number of authors per publication is increasing. To determine whether authorship trends in the North American neurosurgical literature parallel trends observed in other areas of the biomedical literature, I studied original neurosurgical research articles published in the past 50 years. METHODS I sampled clinical, anatomic, and laboratory investigations in Neurosurgery and the Journal of Neurosurgery at 10-year intervals from 1945 to 1995. For each research article, I determined the number of authors, the countries of origin, and the educational degrees of the authors. RESULTS The mean number of authors per article has increased steadily in the past 50 years, from 1.8 (standard deviation, +/-0.8) authors per article in 1945 to 4.6 (standard deviation, +/-2.1) authors in 1995. The proportion of single-author articles is decreasing; these articles accounted for 43% of articles in 1945 and only 3% of articles in 1995. Increases in the proportions of non-M.D. authors and of articles originating outside the United States were also observed. CONCLUSION The proliferation of multiauthor articles and the decrease in the proportion of single-author articles in the neurosurgical literature parallel trends observed in many other areas of biomedical research. Possible explanations include larger research teams, variable or absent journal criteria for defining authorship, and the increased awarding of "gift" authorships.
TOWARDS A CLOUD-BASED DESIGN AND MANUFACTURING PARADIGM: LOOKING BACKWARD, LOOKING FORWARD

The rise of cloud computing is radically changing the way enterprises manage their information technology (IT) assets. Considering the benefits of cloud computing to the information technology sector, we present a review of current research initiatives and applications of the cloud computing paradigm related to product design and manufacturing. In particular, we focus on exploring the potential of utilizing cloud computing for selected aspects of collaborative design, distributed manufacturing, collective innovation, data mining, semantic web technology, and virtualization. In addition, we propose to expand the paradigm of cloud computing to the field of computer-aided design and manufacturing and propose a new concept of cloud-based design and manufacturing (CBDM). Specifically, we (1) propose a comprehensive definition of CBDM; (2) discuss its key characteristics; (3) relate current research in design and manufacture to CBDM; and (4) identify key research issues and future trends.© 2012 ASME
Plant collectors in Ecuador: Camp, Prieto, JØrgensen and Giler

The itinerary of W. H. Camp and his assistants in Ecuador has been reconstructed from fieldbooks deposited in the archives of the library at The New York Botanical Garden. The visited localities are listed according to collection numbers, an alphabetical list of the localities with geographical coordinates or best approximation is provided, and a map is presented showing the area where most numbers were collected.
Parenting practices and problem behavior across three generations: Monitoring, harsh discipline, and drug use in the intergenerational transmission of externalizing behavior

Using data from grandparents (G1), parents (G2), and children (G3), this study examined continuity in parental monitoring, harsh discipline, and child externalizing behavior across generations, and the contribution of parenting practices and parental drug use to intergenerational continuity in child externalizing behavior. Structural equation and path modeling of prospective, longitudinal data from 808 G2 participants, their G1 parents, and their school-age G3 children (n = 136) showed that parental monitoring and harsh discipline demonstrated continuity from G1 to G2. Externalizing behavior demonstrated continuity from G2 to G3. Continuity in parenting practices did not explain the intergenerational continuity in externalizing behavior. Rather, G2 adolescent externalizing behavior predicted their adult substance use, which was associated with G3 externalizing behavior. A small indirect effect of G1 harsh parenting on G3 was observed. Interparental abuse and socidemographic risk were included as controls but did not explain the intergenerational transmission of externalizing behavior. Results highlight the need for preventive interventions aimed at breaking intergenerational cycles in poor parenting practices. More research is required to identify parental mechanisms influencing the continuity of externalizing behavior across generations.
Electrostatically tuned DNA adsorption on like-charged colloids and resultant colloidal clustering

The adsorption of λ-DNA on like-charged silica particles and the resultant DNA-colloid complex structures are examined microscopically in this work. Enhanced adsorption of fluorescence labeled DNA on unlabeled silica particles of varied COOH- and NH2-end functionality is observed with the addition of monovalent or divalent salts to aqueous suspensions of constant DNA and colloid concentrations, which results in an apparent fluorescent shell-like structure for DNA-adsorbed silica particles. ζ-potential measurements indicate that the functionalized silica particles have a negative net charge at all varied ionic strengths, suggesting that screened electrostatic repulsion can account for the enhanced adsorption of DNA on like-charged silica particles in high salt aqueous media, despite the possible hydrophobic origin of the adsorption of DNA in low salt media. Additionally, curious DNA-mediated colloid clustering to form colloidal doublets and triplets is observed for the mixed DNA-colloid suspensions. The optimal DNA and salt concentration ranges are explored and a phase diagram is obtained to predict the formation of considerable fractions of DNA-induced colloidal doublet clusters, which could lead to a simple and rapid method for the synthesis of functional colloidal clusters of desirable shape and bio-functionality.
X-ray standing-wave determination of the clean InP(110) surface reconstruction.

The x-ray standing-wave technique through detection of surface-sensitive Auger electrons has determined the surface reconstruction of clean InP(110). Using the back-reflection diffraction geometry from (220) planes, we find the perpendicular displacements of the surface P and In atoms to be +0.18\ifmmode\pm\else\textpm\fi{}0.1 and -0.48\ifmmode\pm\else\textpm\fi{}0.08 \AA{}, respectively, from their unrelaxed bulk positions. The use of low-energy x rays combined with a novel method of data analysis opens the general problem of surface reconstruction to study by this technique.
Time allocation of one- and two-parent mothers

Using data from one- and two-parent households with two children in rural and urban areas of California, this study analyzes time allocation decisions in market work, household work, and leisure activities among single and married mothers. Results of the seemingly unrelated regression procedures indicate that family structure affects time in household work but not market work or leisure activities. Of the socio-demographic variables, only day of the week explains time allocation to household work, market work, and leisure activities among single and married mothers.
Surgical Management of the Walking Child With Developmental Dysplasia of the Hip

Developmental dysplasia of the hip describes an anatomical abnormality of the hip joint in which femoral head and acetabulum have an incongruent relationship, ranging from acetabular dysplasia with insufficient acetabular coverage of the femoral head to complete dislocation. Treatment of the ambulatory child with developmental dysplasia of the hip usually requires a surgical reduction, often combined with a shortening femoral osteotomy and a pelvic osteotomy. This paper describes the techniques employed in the surgical management of a dislocated hip in an ambulatory child.
Statistical radical copolymerization of styrene and methyl methacrylate in a room temperature ionic liquid

Use of a room temperature ionic liquid as the medium for conventional free radical copolymerization of styrene and methyl methacrylate resulted in reactivity ratios that were significantly different from those obtained in conventional organic solvents or in bulk, demonstrating that polymerization in this alternative medium offers potential to create copolymers having new monomer sequences.
Extracting signal frequency information in time/frequency domain by means of continuous wavelet transform

In this paper, the techniques for extracting signal frequency information in time/frequency domain by means of continuous wavelet transform are presented and the novel "maximum wavelet coefficient frequency-time curve" method, together with "sum wavelet coefficient curve" method are proposed to overcome some shortfalls of existing continuous wavelet transform in signal frequency extracting. The experimental data and the Matlab generated data are calculated with continuous wavelet transform, and further analyzed with four wavelet coefficient evaluation methods, including proposed methods, showing different evaluation method characteristics that can be a reference for choosing suitable methods for different applications.
Microbial diversity along a transect of agronomic zones

The diversity of microbial communities constitutes a critical component of good soil-management practices. To characterize the effects of different management practices, molecular indicators such as phospholipid fatty acid (PLFA), denaturing gradient gel electrophoresis (DGGE) and composition of ammonia-oxidizing bacteria were used to analyze bacterial community structure and diversity from four eastern Washington State soils. Samples from four sites were collected representing a transect of high-precipitation to low-precipitation areas that covered different agronomic zones with different management and cropping practices. Biomass amounts estimated from extractable PLFA were significantly higher in the no-till (NT) soil than in the conventional-till (CT) soil. Similarities among the different 16S rDNA DGGE band profiles were analyzed quantitatively using correspondence analysis and this confirmed that the CT soil was the most dissimilar soil. DGGE analysis of 16S rDNA ammonia-oxidizing bacteria from the four soils revealed two identical bands, indicating little effect of agronomic practices and precipitation on these species. A second set of primers, specific for amoA (ammonia monooxygenase) genes, was used to examine ammonia oxidizers in the samples. Six banding patterns (clusters) from amplified rDNA restriction analysis of 16S rDNA fragments were observed after restriction analysis with HinfI. Sequencing of these clones revealed the presence of only Nitrosospira-like sequences. Analysis of the sequences showed that ammonia oxidizers from the NT soil were more diverse compared to those from the CT and conservation reserve program soils. Our data showed that management and agronomic practices had more impact on bacterial community structure than annual precipitation.
An Overview of Combinatorial Methods for Haplotype Inference

A current high-priority phase of human genomics involves the development of a full Haplotype Map of the human genome [23]. It will be used in large-scale screens of populations to associate specific haplotypes with specific complex genetic-influenced diseases. A key, perhaps bottleneck, problem is to computationally infer haplotype pairs from genotype data. This paper follows the talk given at the DIMACS Conference on SNPs and Haplotypes held in November of 2002. It reviews several combinatorial approaches to the haplotype inference problem that we have investigated over the last several years. In addition, it updates some of the work presented earlier, and discusses the current state of our work.
Biomarkers of Aging Prediction of Longevity by Using Age-Sensitive T-Cell Subset Determinations in a Middle-Aged, Genetically Heterogeneous Mouse Population

Seven T-cell subset values were measured in each of 559 mice at 8 months of age, and then again in the 494 animals that reached 18 months of age. The group included virgin males, virgin females, and mated females, and it was produced by using a four-way cross-breeding system that generates genetic heterogeneity equivalent to a very large sibship. An analysis of covariance showed that four T-cell subsets—CD4, CD4 memory, CD4 naive, and CD4 cells expressing P -glycoprotein—were significant predictors ( p , .003) of longevity when measured at 18 months of age after adjustment for the possible effects of gender and mating. The subset marked by CD4 and P -glycoprotein expression showed a significant interaction effect: this subset predicted longevity only in males. Among subsets measured when the mice were 8 months of age, only the levels of CD8 memory cells predicted longevity ( p 5 .016); the prognostic value of this subset was largely limited to mated females. A cluster analysis that separated mice into two groups based upon similarity of T-cell subset patterns measured at 18 months showed that these two groups differed in life expectancy. Specifically, mice characterized by relatively low levels of CD4 and CD8 memory cells, high levels of CD4 naive cells, and low levels of CD4 cells with P -glycoprotein (64% of the total) lived significantly longer (50 days 5 6%; p , .0007) than mice in the other cluster. The results are consistent with the hypothesis that patterns of T-cell subsets vary among mice in a manner than can predict longevity in middle age, and they suggest that these subsets may prove to be useful for further studies of the genetics of aging and age-sensitive traits.
Transitioning pharmacologic therapy from oral agents to insulin for type 2 diabetes

Prospective intervention trials using an intensive therapy approach in patients with either type 1 or type 2 diabetes have provided evidence that achieving tight glycemic control can impede the development and progression of microvascular complications. Treatment of type 2 diabetic patients has revolved around the use of oral agents to improve insulin secretion or tissue sensitization. As therapy turns to the inclusion of insulin - most often in combination with oral agents - the physician and patient must both be prepared for the issues regarding management of an injectable agent. The objective of this article is to review current evidence supporting the benefits of adding insulin therapy to existing oral hypoglycemic regimens of patients for whom these therapies are no longer providing adequate glycemic control. Approaches to initiating insulin therapy and adjusting treatment regimens are discussed, with a view towards making the addition or switch to insulin a simple and achievable next step in treatment.
Benchmarking Performance Improvement Indicators for the Clinical Engineering Department

Performance measurement and Benchmarking have become an integral component of all sectors and the Clinical Engineering (CE) department can not be overlooked. The optimum goal of Benchmarking Performance indicators in the CE department is to continuously strive to improve the quality of the CE department's services upstream, which will consequently lead to a better financial performance downstream. To be successful in this work, I identified mainstream performance indicators essential in making the adjustments needed for improvement of the department's performance. As to the selection of these indicators, an in-depth survey was sent out to over sixty CE directors. The response was analyzed to reveal the top three mainstream performance indicators to be: (a) CE service cost as a percentage of CE inventory value; (b) Total number of preventive maintenance (PMs) completed per month versus total number of PMs scheduled in a month; (c) CE service cost over the last fiscal year versus the total productive (worked) staff hours in that fiscal year. Upon further mathematical analysis of CE department data from the various CE directors, this work would establish substantive Benchmarks that could be used to measure the CE department's performance. Also, this thesis is in the process of developing a software program (Structured Query Language, Macros, etc.) that would extract data from the department's database and use this data to evaluate the performance of the department. I can envisage this work providing valuable indicator figures for continuous performance optimization of CE services.
An Internet without the Internet protocol

The growth of the Internet has brought about many challenges for its critical infrastructure. The DNS infrastructure, which translates mnemonic host names into IP addresses understood by the routers, is frequently the target of cache poisoning attacks. Internet routers are also experiencing alarming growth in their routing table sizes, which may soon make it impossible for them to forward packets quickly enough to meet demand. Further, concerns about IPv4 address space exhaustion loom on the horizon despite the availability of IPv6. In this paper, we take a fresh look at Internet routing and propose a scheme that addresses all of these concerns cleanly. Our scheme forgoes IP addresses entirely and instead uses host names as identifiers in packets. The scalability of routing is ensured by encapsulating these packets in highly aggregated routing locators: we use autonomous system numbers (ASNs), which are already an integral part of inter-domain routing. We present data and experiments to show that a much simpler and scalable routing infrastructure can be designed for a future Internet by using fewer identifiers for its entities.
Reversion to Subgroup J Avian Leukosis Virus Viremia in Seroconverted Adult Meat-Type Chickens Exposed to Chronic Stress by Adrenocorticotrophin Treatment

SUMMARY. Chickens infected with subgroup J avian leukosis virus (ALV J) early in posthatch life develop viremia followed by a neutralizing antibody (Nab) response that may or may not be able to clear the viremia. Occasionally, chickens that do clear viremia by developing an efficient Nab response revert to viremia, and the factors responsible for this reversion are not clear. In this study, it was hypothesized that stress can cause seroconverted viremia-free chickens to revert to viremia. Adult (52-wk-old) male commercial meat-type chickens that were exposed to ALV J at hatch and had since cleared viremia and remained viremia-free for up to 40 wk, when subjected to chronic stress (for 14 days) induced by porcine adrenocorticotrophin (ACTH), reverted to viremia and cloacal shedding (2/6 [33%]). However, chickens that were contact-exposed to ALV J at 32 wk of age and had seroconverted failed to revert to viremia when subjected to similar chronic stress. Stress did not increase the susceptibility of adult me...
Toward a Constitutional School for American Public Administration

A central tenet of The Federalist is that good government depends on good administration. Two hundred and twenty-three years have passed since Publius began writing this extraordinary text. As American democratic institutions have grown larger and more complex than what the founders ever imagined, many of the ideas expressed in The Federalist remain as relevant today as when James Madison, Alexander Hamilton, and John Jay first advanced them in 1787. The author argues that public administration should move toward a constitutional school that would connect the U.S. Constitution with all aspects of American public administration theory and practice. While the author readily acknowledges this new school’s apparent defects, its most important contribution recognizes that the American Constitution matters, and indeed should serve as a lodestar for our entire field.
Thiobarbiturate-reacting Materials in Microorganisms

The amount of thiobarbiturate-reacting material in 51 strains of bacteria and three yeasts was determined. Reactive material was found to be present in all of the gram-negative bacteria examined. It was assumed that the reactive material in this case was primarily 2-keto-3-deoxyoctonate (KDO), an eight-carbon sugar acid which is usually associated with the cell wall lipolysaccharide of members of the Salmonella-Escherichia group. Very little reactive material could be detected in the gram-positive species and yeasts that were examined. When expressed as per cent dry weight, the gram-negative bacteria exhibited about eight times more reactive material than the gram-positive species. It is suggested that the small amount of reactive material detected in gram-positive cells and yeasts is due to compounds other than KDO.
Long-lived sperm in the geothermal bryophyte Pohlia nutans

Non-vascular plants rely on sperm to cross the distance between male and female reproductive organs for fertilization and sexual reproduction to occur. The majority of non-vascular plants have separate sexes, and thus, this distance may be a few millimetres to many metres. Because sperm need water for transport, it has been assumed that sperm lifespans are short and that this type of sexual reproduction limits the expansion of non-vascular plants in terrestrial environments. However, little data is available on the lifespan of sperm in non-vascular plants, and none is available for bryophytes, the group thought to have first colonized terrestrial habitats. Here, we documented the lifespan of sperm of Pohlia nutans, collected from a geothermal spring's area, and tested the effects of variation under environmental conditions on this lifespan. Surprisingly, 20 per cent of the sperm were still motile after 100 h, and sperm lifespan was not significantly affected by temperature variation between 22 and 60°C. Lifespan was significantly affected by sperm dilution and temperatures above 75°C. These results suggest the need to reconsider the importance of sperm motility in bryophyte fertilization.
USF1 and USF2 mediate inhibition of human trophoblast differentiation and CYP19 gene expression by Mash-2 and hypoxia.

In the human placental syncytiotrophoblast, C19 steroids are converted to estrogens by aromatase P450, product of the CYP19 gene. When human cytotrophoblasts, which lack the capacity to express aromatase, are cultured in 20% O2, they spontaneously fuse to form a multinuclear syncytiotrophoblast and CYP19 expression is markedly induced. On the other hand, when cytotrophoblasts are cultured in 2% O2, syncytiotrophoblast differentiation and induction of CYP19 expression are prevented. We previously observed that expression of the transcription factor Mash-2 (mammalian achaete/scute homologue 2), which is elevated in human cytotrophoblasts and maintained at elevated levels by hypoxia, declines with syncytiotrophoblast differentiation. Overexpression of Mash-2 prevents syncytiotrophoblast differentiation and induction of CYP19 expression. In the present study, we observed that unexpectedly immunoreactive Mash-2 protein was localized predominately to the cytoplasm of human cytotrophoblasts. Elevated cytoplasmic levels of Mash-2 were maintained when trophoblasts were cultured in 2% O2 and declined to undetectable levels upon culture in 20% O2. Previously, we found that Mash-2 inhibited CYP19 promoter activity through sequences within a 350-bp region upstream and within placenta-specific exon I.1 containing three E boxes (E1 at −325 bp, 5′-CACTTG-3′; E2 at −58 bp, 5′-CACATG-3′; and E3 at +26 bp, 5′-CACGTG-3′). In this study, we found that trophoblast nuclear protein binding to these E boxes declined with syncytiotrophoblast differentiation in 20% O2 and was induced by hypoxia; however, Mash-2 did not appear to bind to any of these E boxes. On the other hand, the basic helix-loop-helix leucine zipper transcription factors upstream stimulatory factors 1 and 2 (USF1 and USF2) did bind to E2 and E3 but not E1. Nuclear levels of USF1 and USF2 and DNA-binding activity declined with syncytiotrophoblast differentiation and were maintained at elevated levels by hypoxia and overexpression of Mash-2, whereas USF1 mRNA levels were unaffected. Finally, USF1 overexpression in cultured human trophoblasts markedly inhibited endogenous CYP19 expression, differentiation of cultured human trophoblast cells, and CYP19 promoter activity. These findings suggest that increased protein levels and DNA binding of USF1 and USF2 mediate the inhibitory effects of hypoxia and of Mash-2 on CYP19 gene expression in human placenta.
Children who have attentional disorders: interventions.

The treatment of attentional disorders (ADs) has been the subject of much controversy. Sound treatment programs must address a myriad of issues other than the three core symptoms of AD: inattention, impulsivity, and hyperactivity. Intervention programs purportedly leading to positive long-term outcomes have been studied inadequately. The few treatment plans shown to result in long-term improvement in outcome for children and families have used multiple modalities. Such plans integrate medical, psychological, psychosocial, and educational interventions; provide for case management; and educate and empower families as advocates. Very little actually is known about how treatments for ADs interact with each other, and it has been quite difficult to document the advantages of adding psychosocial treatments to psychopharmacologic treatments, although studies are under way to address these issues. Some of the few studies assessing the long-term efficacy of multimodality treatment programs have shown that although drug treatment alone leads to little measurable change, a combination of medication, psychological treatments, and appropriate classroom interventions leads to improved long-term outcomes. These outcomes include a reduction in antisocial behavior, improved social relationships, enhanced academic performance, improved self-esteem, and decreased delinquent behavior. The treatment team for children who have AD should consist of a partnership that includes the child, family, significant school personnel, and the physician.
IASCE: an intelligent assistant to software cost estimation

A CASE (computer-aided software design) tool called IASCE has been developed to help the project manager estimate a proposed project cost. This tool collects accurate data from current software so that researchers can explore new software models and metrics. IASCE also supports multiple software cost estimation models and their corresponding metrics, tractable for project management control, feedback, and learning activities. In addition, IASCE provides for the establishment of project-specific cost models and corporate metrics for the models, permits tracing of these models and metrics throughout the software life cycle via feedback and post mortem evaluation, and offers a mechanism for long-range improvements of software cost estimation. It can be tailored to a specific software development environment. >
Sugar effects on membrane damage during desiccation of pea embryo protoplasts

Desiccation tolerance of protoplasts isolated from germinating pea (Pisum sativum L. cv. 'Alaska') embryonic axes depends, in part, on the osmotic strength and composition of the suspending medium. To determine the reason for this dependence and whether treatment with different solutions results in different types of damage, protoplast recovery and survival were assessed after dehydration to a range of water contents. Protoplasts were derived from germinating axes that had intermediate desiccation tolerance. Protoplasts were isolated and resuspended in buffers containing sucrose/raffinose (85:15, w/w) or sorbitol, which were isotonic or hypertonic to the cells of the embryonic axis, then were flash-dried to a range of water contents. Protoplasts were rehydrated and stained with fluorescein diacetate (FDA) to assess survival and to estimate two types of membrane injury: lysis and the loss of semipermeability. In all treatments, protoplast survival dropped sharply during the initial phase of dehydration due to lysis. Protoplast survival was greater in hypertonic sucrose/raffinose buffer than in isotonic sucrose/raffinose buffer, or in the latter made hypertonic by the addition of sorbitol. When sorbitol was substituted for sucrose/raffinose in either the isolation or desiccation buffer, or both, protoplast survival at intermediate and low hydrations decreased due to a loss of membrane semipermeability. The results indicate that additional sucrose/raffinose is beneficial for the desiccation tolerance of protoplasts, the benefit is not due to a simple osmotic effect, and the benefit is greatest at water contents less than 0.5 g g(-1) DW, where the presence of the sugars appears to protect membrane semipermeability.
Giardia in Beaver (Castor canadensis) and Nutria (Myocastor coypus) From East Texas

We examined the prevalence of Giardia sp. infection in nuisance beaver (Castor canadensis) and nutria (Myocastor coypus) in east Texas. From October 1992 through September 1993, 100 beaver and 30 nutria were collected in routine wildlife management activities conducted by the U.S. Department of Agriculture–Animal and Plant Health Inspection Service–Texas Animal Damage Control Service. Fecal and duodenal mucoid samples were preserved from each animal. Fecal samples were examined for the occurrence of Giardia sp. cysts using the Merifluor® immunoassay detection kit: 30 beaver (30.0%) and 20 nutria (66.7%) were positive for Giardia sp. Duodenal mucoid samples were examined for Giardia sp. trophozoites using trichrome staining, with 26 beaver (26.0%) and 20 nutria (73.3%) testing positive. Combining both techniques resulted in 33 beaver (33.0%) and 22 nutria (73.3%) testing positive for Giardia sp. We found no relationship between Giardia sp. and host age, sex, river system, habitat, county, or season in beav...