cssi/SciSciGPT-SciSciNet huggingface dataset:
The effects of isoproterenol on adenosine cyclic 3', 5'- monophosphate and contractility in isolated smooth muscle cells.

Suspensions of individual smooth muscle cells were isolated by enzymatic digestion of stomach muscle of Bufo marinus. The role of cyclic 39,59-AMP as a mediator of beta adrenergic-induced decreases in the contractility of smooth muscle was assessed by comparison of the time course and dose dependence for the effects of the beta adrenergic agent isoproterenol on both parameters. Drug-induced changes in the contractile state of isolated smooth muscle cells were determined utilizing a Coulter counter. The ability of isoproterenol to inhibit contractions produced by subsequent exposure to the excitatory agent carbamylcholine was used as an index of decreases in contractility. Exposure to isoproterenol for more than 5 sec was necessary to demonstrate significant inhibition of contraction. Maximal effects of isoproterenol were noted after exposure for 15 sec. Basal cyclic AMP levels, calculated from measurements of cyclic AMP content of cell suspensions and intracellular fluid volume, were 4.5 µM. Exposure to isoproterenol for as little as 2.5 sec produced a significant increase in cyclic AMP levels; maximal changes were noted after exposure for 5 sec or more. The changes in cyclic AMP and contractility exhibited similar dose-response curves, with Ed50 values of approximately 0.4 µM. Prior incubation of the cells with theophylline, cyclic AMP, or N6,29-O-dibutyryl cyclic AMP also inhibited contractions induced by carbamylcholine. These findings strongly support the hypothesis that decreases in the contractility of smooth muscle produced by beta adrenergic agents may be mediated by an increase in cyclic AMP. The Coulter counter results also reveal that individual cells are capable of responding to both cholinergic and adrenergic transmitters. Thus it is likely that integration of the cholinergic excitatory and adrenergic inhibitory input to the whole tissue takes place in part, if not entirely, in individual cells.
Gradient methods for stackelberg security games

Stackelberg games are two-stage games in which the first player (called the leader) commits to a strategy, after which the other player (the follower) selects a best-response. These types of games have seen numerous practical application in security settings, where the leader (in this case, a defender) must allocate resources to protect various targets. Real world applications include the scheduling of US federal air marshals to international flights, and resource allocation at LAX airport. However, the best known algorithm for solving general Stackelberg games requires solving Integer Programs, and fails to scale beyond a few (significantly smaller than 100) number of leader actions, or follower types. In this paper, we present a new gradient-based approach for solving large Stackelberg games in security settings. Large-scale control problems are often solved by restricting the controller to a rich parameterized class of policies; the optimal control can then be computed using Monte Carlo gradient methods. We demonstrate that the same approach can be taken in a strategic setting. We evaluate our approach empirically, demonstrating that it can have negligible regret against the leader's true equilibrium strategy, while scaling to large games.
Apo-lipoprotein localization in human atherosclerotic arteries.

A study documenting the localization in human arteries of apoproteins from human plasma high density (HDL), low density (LDL), and very low density (VLDL) lipoproteins was undertaken in light of their possible roles in the pathogenesis and regression of the atherosclerotic process in man. Apo A-I from HDL, apo B from LDL, apo C-III from VLDL were all localized by immunohistochemical techniques to generally the same areas of atherosclerotic lesions. These consisted of certain bands of collagen and elastic fibers in fatty streaks and fibrous plaques, and extracellular pools of neutral lipid in fibrous plaques. Apoproteins were also occasionally present in areas of diffuse intimal thickening in coronary arteries. Extensiveness and frequency of appearance of apo B in atherosclerotic lesions was greatest in type II hyperlipoproteinemics, thus correlating with the plasma apo B levels. Employing an immuno-peroxidase procedure, apo B was localized ultra-structurally in atherosclerotic lesions to the outer surface of spheres ranging in diameter between 250 and 700 A. These spheres, localized predominantly in lipid cores and between collagen bands, were also seen in negatively-stained preparations of arterial extracts which also reacted positively against anti-apo B, suggesting that the spheres may represent native LDL and VLDL. The superimposed localization of apo A-I, apo B, and apo C-III in atherosclerotic lesions suggests that a specific interaction exists between certain lesion components and these apoproteins.
Inconvenient and Unnecessary? Regulations in the U.S. Taxi Industry

A Certificate of Public Convenience and Necessity (CPCN) is a common requirement for a new business owner in services such as utilities, communications, healthcare, and transportation. However, studies have called into question the effectiveness and purpose of these laws when applied in certain industries. This study chronicles the development of and justifications provided for the enactment of CPCN laws. It then empirically tests the effectiveness of these laws in the taxi industry. This paper finds no evidence that the CPCN laws in the taxi industry are meeting their objectives. Some evidence suggests that CPCN laws achieve the opposite of their intention.
Optimization of in-space supply chain design using high-thrust and low-thrust propulsion technologies

In-space propellant supply chain can be effectively established for manned missions if high-thrust crew vehicles and cargo tugs can be used in conjunction with low-thrust cargo tugs. Optimizing the...
Cancer-Related Pain in Childhood

More than one million Americans are diagnosed annually with cancer. In adults and in children ages 1–4 years, cancer is the second and third most common cause of death, respectively. Cancer accounts for more than 1/2 million deaths each year. It has been reported that procedural pain due to cancer-related diagnostic and treatment measures is a greater problem for children than pain due to disease. However, studies show 50–78% of children experience pain as a presenting symptom at the time of oncological diagnosis (Miser et al. 1987). With disease progression, greater than 89% of children experience pain in advanced stages (Sirkia et al. 1998). Pain is one of the most feared aspects of cancer and has led to fierce debates regarding euthanasia in adults. Recent rulings in the Netherlands allows euthanasia in children aged 12 years or less, with newborns inclusive, if they are deemed to have incurable disease and unbearable suffering (ZENIT 2004). A debate of medical ethics on pediatric euthanasia is beyond the scope of this chapter. However, with concerted efforts, up to 90% of cancer patients with pain can have adequate analgesia by non-invasive measures. With the institution of the World Health Organization Guidelines on Cancer Pain Relief and Palliative Care in Children most patients can experience respite from pain (McGrath 1996).
Efficient validation testing of Through-Silicon-Via (TSV) ASICs for CZT x-ray detectors

The High Resolution Energetic X-ray Imager (HREXI ) is a coded-aperture imaging telescope that utilizes a large closely-tiled array of CdZnTe (CZT) detectors, each 19.9 x 19.9 x 3mm with a 32 x 32 pixel (604μm) for coded aperture X-ray imaging (3 - 200 keV) of cosmic X-ray sources and transients. Each CZT crystal is read out by an ASIC incorporating, for the first time, Through Silicon Vias (TSVs). These TSVs replace the wire bonds for this ASIC, originally designed for the Nuclear Spectroscopic Telescope Array (NuSTAR) focusing hard X-ray telescope. The TSVs allow flip-chip bonding of the ASIC to the PCB board electronics for processing of the data. The new TSV-ASICs will enable closer tiling and larger imaging arrays which require faster, more efficient ASIC testing and calibration at the die level. We have designed and developed an ASIC Test Stand (ATS) for rapid ASIC testing prior to bonding to CZT. We demonstrate how ASIC die-level testing with the ATS can be performed rapidly with rigidly spaced micro-pogo pins supported by an FPGA readout.
Development of a Human APOE Knock-in Mouse Model for Study of Cognitive Function After Cancer Chemotherapy

Cancer-related cognitive impairment in breast cancer patients exposed to multi-agent chemotherapy regimens is associated with the apolipoprotein E4 (APOE4) allele. However, it is difficult to determine the effects of specific agents on cognitive impairment in human studies. We describe the development of a human APOE knock-in congenic C57BL/6J mouse model to study cancer-related cognitive impairment. Female APOE3 and APOE4 homozygous mice were either left untreated or treated with the most commonly used breast cancer therapeutic agent, doxorubicin. APOE3 and APOE4 mice had similar behaviors in exploratory and anxiety assays, which were affected transiently by doxorubicin treatment. Spatial learning and memory were measured in a Barnes maze: after 4 days of training, control APOE3 and APOE4 mice were able to escape with similar latencies. In contrast, doxorubicin-treated APOE4 mice had markedly impaired learning compared to doxorubicin-treated APOE3 mice at all time points. Voxel-based morphometry of magnetic resonance images revealed that doxorubicin treatment caused significant changes in the cortex and hippocampus of in both APOE3 and APOE4 mouse brains, but the differences were significantly greater in the APOE4 brains. The results indicate that doxorubicin-exposed APOE4 mice recapitulate key aspects of human cancer-related cognitive impairment. These data support the usefulness of this novel preclinical model for future elucidation of the genetic and molecular interactions of APOE genotype with chemotherapy; this model can also allow extension to prospective studies of older mice to study these interactions in the context of aging.
Elective nodal irradiation with simultaneous integrated boost stereotactic body radiotherapy for pancreatic cancer: Analyses of planning feasibility and geometrically driven DVH prediction model

Purpose We evaluate the feasibility of the elective nodal irradiation strategy in stereotactic body radiotherapy (SBRT) for pancreatic cancer. Methods Three simultaneous integrated boost (SIB)-SBRT plans (Boost1, Boost2, and Boost3) were retrospectively generated for each of 20 different patients. Boost1 delivered 33 and 25 Gy to PTV1 and PTV2, respectively. Boost2 delivered 40, 33, and 25 Gy to boostCTV, PTV1, and PTV2, respectively. Boost3 delivered 33 and 25 Gy to PTV1 and PTV3, respectively. PTV1 covered the initial standard SBRT plan (InitPlan) gross tumor volume (GTV). PTV2 covered CTVgeom which was created by a 10-mm expansion (15 mm posterior) of GTV. PTV3 covered CTVprop which included elective nodal regions. The boostCTV included GTV as well as involved vasculature. The planning feasibility in each scenario and dose-volume histograms (DVHs) were analyzed and compared with the InitPlan (delivered 33 Gy only to PTV1) by paired t-test. Next, a novel DVH prediction model was developed and its performance was evaluated according to the prediction accuracy (AC) of planning violations. Then, the model was used to simulate the impacts of GTV-to-organs at risk (OAR) distance and gastrointestinal (GI) OAR volume variations on planning feasibility. Results Significant dose increases were observed in GI-OARs in SIB-SBRT plans when compared with InitPlan. All dose constraints were met in 63% of cases in InitPlan, Boost1, and Boost2, whereas Boost3 developed DVH violations in all cases. Utilizing previous patient anatomy, the novel DVH prediction model achieved a high AC in the prediction of violations for GI-OARs; the positive predictive value, negative predictive value, and AC were 66%, 90%, and 84%, respectively. Experiments with the model demonstrated that the larger proximity volume of GI-OAR at the shorter distance substantially impacted on planning violations. Conclusions SIB-SBRT plan with geometrically defined prophylactic areas can be dosimetrically feasible, but including all nodal areas with 25 Gy in five fractions appears to be unrealistic.
Are We Maximizing the Role of Caregivers’ Support Networks in Early Intervention?

Part C Early Intervention is intended to build capacity among caregivers of infants and toddlers with special needs to use tailored strategies in natural environments. Satisfaction and perceived st...
Recurrent Neural Network-Assisted Adaptive Sampling for Approximate Computing

We propose an adaptive signal sampling approach that dynamically adjusts the sampling rate to approximate the local Nyquist rate of the signal. The proposed adaptive sampling approach consists of a recurrent neural network-based change detector that detects the point of frequency change and a local Nyquist rate estimator based on a multi-rate signal processing scheme. We empirically demonstrate that our adaptive sampling approach significantly reduces the overall sampling rate for various types of signals and therefore improves the computational efficiency of subsequent signal processing.
Size Does Not Matter: The Outdated Practice of Using Oversized Organs for Recipients with Elevated PVR

Purpose Elevated pulmonary vascular resistance (PVR) continues to pose challenges in heart transplantation, but does the common belief that implanting a larger organ when the PVR is high actually affect outcomes? The purpose of this study is to assess post-transplantation outcomes in recipients with increased PVR in relation to donor organ size. Methods The United Network for Organ Sharing (UNOS) database was used to identify patients ages 0-18 years at time of listing who underwent transplantation between 2010 and 2019 and for whom cardiac catheterization and donor-recipient weight data was available. Patients were divided by listing PVR into 6 Wood units. Donor-Recipient weight ratio was categorized as undersized (≤0.80), mid-size (0.81-1.2), and oversized (>1.2). Subgroup analysis was done with an additional supersized group (>2.0). Results 1491 patients met study criteria. Median age [years (IQR)] 10 (3-15) and 45% female. 4% of heart transplantation cases used undersized, 45% used mid-size, and 51% used oversized organs. More patients with PVR>6 were transplanted with an oversized organ compared to patients with PVR 6 at listing who were transplanted with an oversized organ versus those transplanted with an undersized (p=0.359) or mid-sized (p=0.956) organ. In subgroup analysis, even in patients transplanted with a supersized organ, there was no survival difference noted regardless of PVR. Conclusion Despite a persistent practice pattern to transplant high PVR patients with oversized organs, there remains no difference in post-transplantation survival between these patients and those transplanted with smaller organs. Therefore, transplants in patients with high PVR should not be delayed by waiting for larger organs.
Impact of standardized prenatal documentation among newborns with ductal-dependent heart disease.

Absent risk stratification, variable physiology of ductal-dependent congenital heart disease (DD-CHD) imparts risk of over-medicalization and unnecessary exclusion from early parental bonding. Single-center retrospective cohort study of term infants with isolated prenatally diagnosed DD-CHD expected to require immediate advanced resuscitation/intervention (2005–2017). Standardized documentation (2015 onward) included diagnosis, expected saturations, and allowability of postnatal parental bonding. The study cohort (n = 386) included 289 patients in the pre-standardized documentation era and 97 in the post-era; the groups had similar characteristics. Fewer infants were born by cesarean in the later era (32% vs. 22%; p = 0.049). Decrease in any respiratory intervention (38–26%; p = 0.03) followed standardized documentation. More patients had any bonding time (22–74%; p < 0.0001), without increase in CPAP or intubation in the first two hours of life (6.9% vs. 7.2%; p = 0.92). Standardized predelivery documentation for neonates with DD-CHD decreased unnecessary respiratory intervention and increased parental bonding. This is a ductal-dependent lesion and the baby will need prostaglandin infusion to maintain a patent ductus arteriosus to provide systemic blood flow. Given that the lesion is ductal dependent,we would recommend neonatology attendance at delivery with initial stabilization and treatment of the infant in the NEST (Newborn Evaluation, Stabilization, and Treatment Room) with prostaglandin initiation, umbilical line placement and an echocardiogram prior to admission to the PCTU (Pediatric Cardiothoracic ICU). We anticipate that the baby will be stable from a cardiovascular standpoint at delivery and for a short time thereafter as the ductus arteriosus will be open. Initial oxygen saturations above 75% are acceptable for this heart lesion. Therefore, if the baby appears well in the delivery room we would encourage a lot of family a brief period of time for appearance parent-baby bonding either before initial assessment in the NEST or after initial assessment in the NEST and prior to line placement.
The “wicked problem” of technology and teacher education: Examining teacher educator technology competencies in a field-based literacy methods course

This paper paints a complex portrait of the “wicked problem” of teaching technology integration in a field-based content literacy course in order to analyze how a teacher educator demonstrated a pr...
Mounting a Regional Response to the COVID-19 Pandemic: Another Reason to "Keep" Your Lab.

CONTEXT.­: Declining reimbursement shifts hospital laboratories from system assets to cost centers. This has resulted in increased outsourcing of laboratory services, which can jeopardize a hospital systems' ability to respond to a health care crisis. OBJECTIVES.­: To demonstrate that investment in a core laboratory serving an academic medical center equipped a regional health system to respond to the Coronavirus disease 2019 (COVID-19) pandemic. DESIGN.­: COVID-19 diagnostic testing data were analyzed. Volumes were evaluated by result date (March 16, 2020-May 6, 2020), and the average of received-to-verified turnaround time was calculated and compared for in-house and send-out testing, and different in-house testing methodologies. RESULTS.­: Daily viral diagnostic testing capacity increased by greater than 3000% (from 21 tests per day to 658 tests per day). Total viral diagnostic testing reported by the core laboratory increased by 128 times during 22 days of test method validation and 826 times during the analysis period, while average turnaround time per day for send-out testing increased from 3.7 days to 21 days. Decreased overall average turnaround time was observed at the core laboratory (0.45 days) versus send-out testing (7.63 days) (P < .001). CONCLUSIONS.­: Investment in a core laboratory provided the health system with the necessary expertise and resources to mount a robust response to the pandemic. Local access to testing allowed rapid triage of patients and conservation of scarce personal protective equipment (PPE). In addition, the core laboratory was able to support regional health departments and several hospitals outside of the system.
Magnetic field as a trigger of carotenoid production by Phaffia rhodozyma

Abstract This study aimed to evaluate the influence of magnetic fields (MF) on inoculum cultivation and carotenoid production by Phaffia rhodozyma. The application of MF in the inoculum culture was evaluated (0 m T – control and 30 m T). Cellular concentration increased by 12.8 % after 24 h-culture with MF application compared to the control assay, and this was the best alternative for the preparation of inoculum. Different intervals of MF application were evaluated over 168 h. The highest volumetric carotenoids concentration was achieved by applying MF throughout cultivation, with values of 1146.39 ± 26.18 μg L−1 and carotenoid productivity of 11.94 ± 1.11 μg L−1 h−1 in 96 h. As a result, carotenoid production increased by 59.4 % and carotenoid productivity by 99.3 %. This study is one of the first to consider MF application in carotenoid production using P. rhodozyma as a viable and low-cost alternative for carotenoid production in a shorter cultivation time.
Paperspray Ionization Mass Spectrometry as a Tool for Predicting Real-Time Optimized Dosing of the Chemotherapeutic Drug Melphalan.

BACKGROUND Melphalan, an important component of hematopoietic stem cell transplantation (HSCT) preparative regimens, is associated with significant toxicity and large between patient variability in pharmacokinetics making it difficult to calculate the optimal dose for pediatric patients. Paperspray (PS) ionization generates gas phase analyte ions directly from a dried blood spot without the need for prior sample preparation or chromatography. With these advantages, a validated PS-MS/MS assay was developed and applied to the 'real-time' determination of melphalan pharmacokinetics (PK). METHODS Melphalan was quantified by stable-labeled isotope dilution analysis in whole blood by PS-MS/MS. Blood samples were obtained at timed intervals from patients during HSCT after administration of a very low (test) dose of melphalan to avoid toxicity. Pharmacokinetics parameters were calculated using WinNonlin v.6.4. From these data, the optimal therapeutic dose was estimated and full dose PK repeated. RESULTS PS-MS/MS method was linear over a large dynamic range (25-50 000 ng/mL), intra- and interassay reproducibility of quality control samples was <15% CV. With essentially no prior sample preparation, PS-MS/MS measurement of blood melphalan concentrations showed excellent correlation (R2 = 0.959, n = 62) with a validated electrospray-LC-MS/MS method. Trapezoidal area under the curves calculated for 5 patients administered low dose melphalan showed a high linear correlation (R2 = 0.981) between the PS-MS/MS and LC-MS/MS methods. The faster PS approach permitted real-time PK evaluation of individual patients. CONCLUSIONS A validated PS-MS/MS assay for melphalan in patients undergoing HSCT is described that facilitates pharmacokinetic-guided individualized precision dosing with immediate bedside dose adjustments to improve outcomes by balancing toxicity and efficacy of melphalan.
Keras2c: A library for converting Keras neural networks to real-time compatible C

Abstract With the growth of machine learning models and neural networks in measurement and control systems comes the need to deploy these models in a way that is compatible with existing systems. Existing options for deploying neural networks either introduce very high latency, require expensive and time consuming work to integrate into existing code bases, or only support a very limited subset of model types. We have therefore developed a new method called Keras2c, which is a simple library for converting Keras/TensorFlow neural network models into real-time compatible C code. It supports a wide range of Keras layers and model types including multidimensional convolutions, recurrent layers, multi-input/output models, and shared layers. Keras2c re-implements the core components of Keras/TensorFlow required for predictive forward passes through neural networks in pure C, relying only on standard library functions considered safe for real-time use. The core functionality consists of ∼ 1500 lines of code, making it lightweight and easy to integrate into existing codebases. Keras2c has been successfully tested in experiments and is currently in use on the plasma control system at the DIII-D National Fusion Facility at General Atomics in San Diego.
Destination Transplant: Protocol for a Parallel-group Randomized Trial of an Educational Intervention to Increase Kidney Transplant Among Black People on the Transplant Waiting List.

For most patients with kidney failure, living donor kidney transplant (LDKT) is their best treatment option. Compared with White people, Black people are more likely to have kidney failure but less likely to receive LDKTs. In this study, the investigators will test an educational intervention, Destination Transplant, designed to reduce this disparity, among Black people already listed for kidney transplant. Methods The investigators will conduct a parallel group, 2-arm randomized clinical trial among 500 Black kidney transplant candidates. The main objective of this study is to test an educational and behavioral intervention that is designed to increase receipt of LDKT among transplant candidates (persons active on the deceased donor kidney transplant waiting list) who are Black. Candidates on the kidney transplant waiting list will be randomly assigned to 1 of 2 conditions: (1) a control group that will receive Usual Care, or (2) an Intervention group that will receive Destination Transplant, a 9-month intervention that includes an in-person group-based education session, postcards at monthly intervals, and a follow-up phone call from a transplant educator. At baseline and during 18 months of follow-up, demographic and clinical variables will be collected, as well as variables such as transplant derailers (factors that might be sources of delay, difficulty, or challenge to pursuing transplant), transplant knowledge, and health literacy, small steps taken to pursue LDKT, readiness for LDKT, decisional balance and self-efficacy LDKT, decisional conflict, family support, availability of potential living donors, and general health status. Conclusions This educational intervention aims to increase both readiness to pursue LDKT and actual receipt of LDKTs among Black and African American patients who are already on the kidney transplant waiting list. The aim of the intervention is to reduce racial disparities in access to LDKT.
Design and analysis of a 2-year parallel follow-up of repeated ivermectin mass drug administrations for control of malaria: Small sample considerations for cluster-randomized trials with count data:

Background:Cluster-randomized trials allow for the evaluation of a community-level or group-/cluster-level intervention. For studies that require a cluster-randomized trial design to evaluate clust...
Intrahepatic Cholangiocarcinoma: A Summative Review of Biomarkers and Targeted Therapies

Although rare, intrahepatic cholangiocarcinoma (ICC) is the second most common primary hepatic malignancy and the incidence of ICC has increased 14% per year in recent decades. Treatment of ICC remains difficult as most people present with advanced disease not amenable to curative-intent surgical resection. Even among patients with operable disease, margin-negative surgical resection can be difficult to achieve and the incidence of recurrence remains high. As such, there has been considerable interest in systemic chemotherapy and targeted therapy for ICC. Over the last decade, the understanding of the molecular and genetic foundations of ICC has reshaped treatment approaches and strategies. Next-generation sequencing has revealed that most ICC tumors have at least one targetable mutation. These advancements have led to multiple clinical trials to examine the safety and efficacy of novel therapeutics that target tumor-specific molecular and genetic aberrations. While these advancements have demonstrated survival benefit in early phase clinical trials, continued investigation in randomized larger-scale trials is needed to further define the potential clinical impact of such therapy.
Interlocus gene conversion explains at least 2.7 % of single nucleotide variants in human segmental duplications

Interlocus gene conversion (IGC) is a recombination-based mechanism that results in the unidirectional transfer of short stretches of sequence between paralogous loci. Although IGC is a well-established mechanism of human disease, the extent to which this mutagenic process has shaped overall patterns of segregating variation in multi-copy regions of the human genome remains unknown. One expected manifestation of IGC in population genomic data is the presence of one-to-one paralogous SNPs that segregate identical alleles. Here, I use SNP genotype calls from the low-coverage phase 3 release of the 1000 Genomes Project to identify 15,790 parallel, shared SNPs in duplicated regions of the human genome. My approach for identifying these sites accounts for the potential redundancy of short read mapping in multi-copy genomic regions, thereby effectively eliminating false positive SNP calls arising from paralogous sequence variation. I demonstrate that independent mutation events to identical nucleotides at paralogous sites are not a significant source of shared polymorphisms in the human genome, consistent with the interpretation that these sites are the outcome of historical IGC events. These putative signals of IGC are enriched in genomic contexts previously associated with non-allelic homologous recombination, including clear signals in gene families that form tandem intra-chromosomal clusters. Taken together, my analyses implicate IGC, not point mutation, as the mechanism generating at least 2.7 % of single nucleotide variants in duplicated regions of the human genome.
Specificity and Role in Cholesterol Biosynthesis of a Squalene and Sterol Carrier Protein

Abstract A purified (300-fold) liver protein specifically binds squalene and sterol precursors of cholesterol and activates (4-fold or greater) the microsomal enzymic steps of cholesterol biosynthesis in which these precursors participate. This heat-stable protein appears to play a general role as vehicle for cholesterol and its water-insoluble precursors, i.e. it is a squalene and sterol carrier protein (SCP). Apo-SCP (molecular weight 16,000) aggregates to a higher molecular weight species (g150,000) during binding of squalene or sterols and yields a noncovalent squalene- or sterol-SCP complex. Apo-SCP similarly binds stoichiometric levels of a cholesterol precursor and the pyridine nucleotide cofactor required for the oxidation or reduction of the precursor by microsomal enzymes. The apparent Km for a particular sterol-SCP complex is markedly lower than that for initially unbound sterol, although the maximum rate of the particular reaction is unchanged. Of the other liver and serum proteins tested, only apo-high density lipoprotein (HDL) will substitute for the binding and activation functions of apo-SCP. A component of HDL may be identical with apo-SCP.
Virtualization aware file systems: getting beyond the limitations of virtual disks

Virtual disks are the main form of storage in today's virtual machine environments. They offer many attractive features, including whole system versioning, isolation, and mobility, that are absent from current file systems. Unfortunately, the low-level interface of virtual disks is very coarse-grained, forcing all-or-nothing whole system rollback, and opaque, offering no practical means of sharing. These problems impose serious limitations on virtual disks' usability, security, and ease of management. To overcome these limitations, we offer Ventana, a virtualization aware file system. Ventana combines the file-based storage and sharing benefits of a conventional distributed file system with the versioning, mobility, and access control features that make virtual disks so compelling.
Growth of Physarum flavicomum and Physarum rigidum in Chemically Defined Minimal Media

Physarum flavicomum, P. polycephalum, and P. rigidum grew at pH 4.2 in a medium composed of mineral salts, glucose, biotin, thiamine, hematin, and four amino acids. Important differences in pH tolerance were noted among the species. The minimal medium of P. flavicomum and P. polycephalum contained the amino acids methionine, glycine, and arginine, but valine was also required by P. rigidum. Starting with an inoculum of about 0.3 mg of protein per 25 ml of minimal medium, P. flavicomum and P. polycephalum grew to 23 mg and P. rigidum to 12 mg of protein per 25 ml in 3, 2, and 4 weeks, respectively. P. flavicomum and P. polycephalum grew with valine or leucine replacing arginine in the minimal medium but the growth yields and growth rates were decreased. All three species utilized homocysteine thiolactone in the minimal media in place of methionine. Serine adequately replaced glycine for P. rigidum but was inhibitory in the minimal medium of P. flavicomum or P. polycephalum unless homocysteine thiolactone also replaced methionine. Growth rates of all three organisms were increased in the presence of seven amino acids (original four plus leucine, lysine, and isoleucine).
A falling ball apparatus to measure filament cross-linking.

Publisher Summary This chapter describes a low shear falling ball viscometer that can be used to measure consistency changes in cellular extracts and the gelation of actin filament networks. It is particularly useful for routine assays of actin filament interactions during the purification of molecules that either promote or inhibit the network formation. Although this device cannot yet be used for rigorous quantitative analysis, the assay does have a number of practical advantages over other routine assays. The falling ball apparatus consists of a capillary tube containing the sample and a steel ball that will fall through the sample, provided that the yield strength of the material is low enough. The force balance in the system and Stokes' equation yield an expression relating the observed velocity of the ball to the absolute viscosity of Newtonian samples and the apparent viscosity of non-Newtonian samples. The ball centrifugation assay is a simple approach to measuring yield strength. Its major limitations are some uncertainty about the value of the geometrical constant and the crude, stepwise application of force by centrifugation. A better method would be to observe the ball continuously as the centrifugal force is gradually increased.
The Northern Hardwood Ecosystem at Hubbard Brook in Relation to Other Forested Ecosystems in the World

Forests and woodlands cover some 57 × 106 km2, which is about 38% of the total continental area or 11% of the earth’s surface. Despite this relatively small area, 92% of the earth’s plant biomass and 46% of its annual net primary production come from forests (Table 21). The 79.9 billion metric tons of dry plant matter produced (net) each year by forests exceeds the total net primary production of the oceans, even though the oceans are more than six times larger in area. The animal biomass in these forests represents 68% of the total found on continental land masses (Whittaker and Likens, 1973).
Heat transfer in a jet over a sinusoidally rotating disc and an oscillating plate

Abstract A perturbation analysis is presented for a weak jet over a disc rotating with a velocity varying sinusoidally about a nonzero mean and a wall jet impinging normally over an oscillating plate. The constant wall temperature boundary condition has been considered. Numerical results for the universal functions for the velocity and temperature fields are given. The missing wall derivatives of the velocity functions and thermal functions for Prandtl numbers ranging from 0.01 to 100, have been tabulated.
Measuring the impact of mitigation activities on flood loss reduction at the parcel level: the case of the clear creek watershed on the upper Texas coast

As property damage from flooding continues to increase, particularly in coastal areas, the adoption of strategies to mitigate these losses has never been more important to protecting the health and safety of coastal communities. Both structural and non-structural flood mitigation activities are being considered to buffer the adverse consequences of building structures in areas exposed to flood risk. However, little research has been conducted on the effectiveness of flood mitigation practices, particularly non-structural approaches at the parcel level. Our study addresses this lack of critical knowledge by examining the effect of mitigation activities adopted under the FEMA community rating system on insured property losses across multiple communities within the Clear Creek watershed located just south of Houston, TX and adjacent to Galveston Bay. Specifically, we statistically identify the degree to which various mitigation strategies adopted by a community reduce flood loss claims among 9,555 parcels from 1999 to 2009. Results indicate that several mitigation policies adopted at the community level result in significant savings in property damage for homeowners in the Clear Creek watershed.
Warped unification, proton stability, and dark matter.

We show that solving the problem of baryon-number violation in nonsupersymmetric grand unified theories (GUT's) in warped higher-dimensional spacetime can lead to a stable Kaluza--Klein particle. This exotic particle has gauge quantum numbers of a right-handed neutrino, but carries fractional baryon number and is related to the top quark within the higher-dimensional GUT. A combination of baryon number and $\mathrm{S}\mathrm{U}(3)$ color ensures its stability. Its relic density can easily be of the right value for masses in the 10 GeV--few TeV range. An exciting aspect of these models is that the entire parameter space will be tested at near future dark matter direct detection experiments. Other exotic GUT partners of the top quark are also light and can be produced at high energy colliders with distinctive signatures.
Homelessness in Berlin: Between Americanization and Path Dependence

This study examines the potential Americanization of homelessness and homeless policy in post-Unification Berlin in light of recent neoliberal policy reforms and simultaneously declining levels of homelessness. Drawing upon original ethnographic research from the late 1990s, secondary sources, and key informant interviews, it is shown that partial Americanization exists in that homeless people find themselves displaced from the commercial center, contained and warehoused in poor areas surrounding the center, and subject to substandard welfare, service, and shelter provision. The harshest consequences, however, are ameliorated by the still-existing, more comprehensive welfare system that, abetted by slowed urban rental markets, is more effectively used to facilitate homeless people's re-entry into the housing market. Given that the new workfare policies facilitate the formation of a new class of working poor, the long-term prospects of homeless people remain grim, especially after the economy begins its ne...
A 3T external source quadrupole Fourier transform mass spectrometer for ion/molecule reactions and analysis

Abstract A versatile quadrupole Fourier transform mass spectrometry instrument for both ion/molecule chemistry and analysis is described. Preliminary results show that despite the relatively low field (3T), a large mass range (up to m/z 16 000) and high resolution (41 000 FWHH at m/z 1692) are obtained. Metal ions (e.g. Fe + ) for ion/molecule chemistry and organic ions (e.g. maltose) for analysis are routinely produced via secondary ion mass spectrometry (and liquid secondary ion mass spectrometry) in the external source.
Comparison of mixed and pure gas permeation characteristics for CO2 and CH4 in copolymers and blends containing methyl methacrylate units

Abstract Permeation of pure CO2 and CH4 and their 50 50 mixtures (at 5 and 20 atm partial pressures) were measured at 35°C in a series of styrene/methyl methacrylate copolymers, SMMA, and a series of miscible blends of bischloral polycarbonate, BCPC, and poly(methyl methacrylate), PMMA. PMMA is significantly plasticized by CO2 at 20 atm; whereas, BCPC and, to a lesser extent, polystyrene are not. Thus, by incorporating MMA units into the copolymer or in the blend, a varying extent of plasticization response was built in. Mixed gas separation factors were found to be well-predicted by pure gas measurements for CO2 and CH4 at 5 atm partial pressure for all copolymers and all blends. However, at 20 atm partial pressure of CO2, the actual mixed gas separation factors are much lower than that predicted by pure gas measurement as the MMA content of the copolymers or the blends increased. Significant history or conditioning effects accompany plasticization in glassy polymers so the results obtained depend on the measurement protocol. For this reason, no attempt was made to fit these data to current models since they do not allow for this fact.
Comparison of the cigarette dependence scale with four other measures of nicotine involvement: correlations with smoking history and smoking treatment outcome in smokers with substance use disorders.

Abstract The Cigarette Dependence Scale (CDS) was developed to assess principal aspects of smoking dependence. In a French longitudinal survey, CDS showed stronger relationships to urge and change in smoking rate than the Fagerstrom Test for Nicotine Dependence (FTND). Neither measure predicted abstinence at follow-up in that survey but there was no treatment or cessation induction. The present study investigated concurrent and predictive validity of the CDS in a treatment population by comparing the CDS to the FTND and other measures of tobacco involvement as (1) a correlate of smoking and cessation history and (2) a predictor of short-term smoking abstinence among smokers with substance use disorders (SUD) receiving smoking treatment. Methods : Smokers (10 + cigarettes per day) in substance treatment received brief advice and nicotine patch for 8 weeks; half also received contingent vouchers for smoking cessation. Assessments were conducted pretreatment and 7, 14 and 30 days after treatment initiation, with abstinence verified biochemically. Results : At baseline (n = 305), the 12-item and 5-item CDS versions showed excellent and marginal reliability, respectively. FTND shared 43 and 61% of variance with CDS-12 and CDS-5, respectively. FTND and CDS scales correlated positively with cigarettes per day, and negatively with time to first cigarette, motivation to quit and age at first daily smoking. Only CDS correlated with the number of past quit attempts. Neither CDS nor FTND predicted abstinence within treatment, unlike the motivation measure and time to first cigarette. Conclusion : In moderate-heavy smokers with SUD in smoking treatment in the U.S., the CDS is largely equivalent to the FTND as an indicator of tobacco dependence but the CDS-5 is less reliable. Motivation was the most consistent predictor of outcome, and time to first cigarette was the only tobacco dependence measure that predicted smoking abstinence during treatment.
Penetration of radioactive phosphorus into normal and shocked rats' brain.

SummaryThe clear outline in our controls around regions bathed by cerebrospinal fluid may be due to P32 after it had passed through the blood cerebrospinal fluid barrier. The diffuse and widespread penetration of P32 into brains of tumbled rats indicates alteration of permeability caused by damage at the blood brain barrier. This penetration can not be seen with usual stain technics nor is it due to dispersion following extensive petechial hemorrhage within the brain substance.
On-Line 1D and 2D Porous Layer Open Tubular/LC-ESI-MS Using 10-μm-i.d. Poly(styrene−divinylbenzene) Columns for Ultrasensitive Proteomic Analysis

Following on our recent work, on-line one-dimensional (1D) and two-dimensional (2D) porous layer open tubular/liquid chromatography-electrospray ionization-mass spectrometry (PLOT/LC-ESI-MS) platforms using 3.2 m × 10 μm i.d. poly(styrene−divinylbenzene) (PS−DVB) PLOT columns have been developed to provide robust, high-performance, and ultrasensitive proteomic analysis. With the use of a PicoClear tee, the dead volume connection between a 50 μm i.d. PS−DVB monolithic micro-SPE column and the PLOT column was minimized. The micro-SPE/PLOT column assembly provided a separation performance similar to that obtained with direct injection onto the PLOT column at a mobile phase flow rate of 20 nL/min. The trace analysis potential of the platform was evaluated using an in-gel tryptic digest sample of a gel fraction (15−40 kDa) of a cervical cancer (SiHa) cell line. As an example of the sensitivity of the system, ∼2.5 ng of protein in 2 μL of solution, an amount corresponding to 20 SiHa cells, was subjected to on-l...
False expectations? Expectations vs. probabilities for dying.

It is widely recognized that the role of the physician has undergone dramatic changes in the last century—changes which have serious implications for the patient-physician relationship. This is an ethnographic study examining how certain changes in the role and abilities of biomedical physicians have affected patient attitudes and expectations about end-of-life care. In-home interviews were conducted with eighteen persons age fifty-five and older, including a sample of Hemlock Society members. Results indicate a broad spectrum of end-of-life concerns including capacity, autonomy, pain, and burden to loved ones. Most participants reported a reluctance to begin a discussion of death or future deteriorating capacity with their physicians. Instead, when conversations about death were reported, they had been largely limited to the scenarios of catastrophic illness (e.g., hospitalization, ventilator, etc.) and the Living Will. While this discussion does not overlook the utility of the Living Will, it proposes t...
The formation and decomposition of KOH on Ru(001)

Abstract Potassium hydroxide is formed when water is adsorbed at 80 K on a Ru(001) surface precovered with potassium. The vibrational spectrum of KOH obtained with EELS is characterized by an OH stretch at 3570–3620 cm −1 ; losses at 1340–1500 cm −1 and 200–800 cm −1 are tentatively assigned to KOH bending and KO stretching vibrations respectively. Heating the surface to 500–600 K results in decomposition of KOH and desorption of the dissociation products. The decomposition pathway is found to depend strongly on the potassium precoverage.