cssi/SciSciGPT-SciSciNet huggingface dataset:
Preclinical modeling of endocrine response and resistance: focus on aromatase inhibitors.

The authors developed a breast cancer intratumoral aromatase model system to compare the antitumor efficacy of several aromatase inhibitors (AIs) and antiestrogens (AEs). Although the AI letrozole caused sustained growth inhibition, tumors eventually began to grow, even when treatment was maintained. For the current study, the mechanisms of resistance to letrozole during the course of treatment were investigated. Estrogen receptor α (ER-α) levels decreased below control levels in letrozole-resistant tumors. The decrease was simultaneous to an increase in phosphorylation of ER-α and an unaltered expression of progesterone receptor (PgR). Expression levels of HER-2, activated (phosphorylated) SHC-adaptor protein (p-Shc), growth factor receptor-bound protein 2 (Grb-2), p-Raf, phosphorylated mitogen-activated protein kinase kinase 1/2 (p-Mekl/2), and phosphorylated mitogen-activated protein kinase (p-MAPK) were increased. When cells isolated from letrozole-resistant tumors (LTLTCa cells) were treated with inhibitors of the HER-2 signaling pathway, ER-α expression and estradiol-stimulated transactivation was restored. The HER-2 blocker trastuzumab also restored the sensitivity of LTLTCa cells to AIs and AEs. These findings suggested that there is crosstalk between ER and HER-2 signaling. To prevent activation of the HER-2 pathway and resistance to AIs, mice were treated with a combination of AIs and the ER down-regulator fulvestrant. There was no increase in HER-2 or p-MAPK expression, and tumor growth was inhibited significantly. When trastuzumab was added to unresponsive tumors under letrozole treatment, it significantly inhibited tumors growth compared with switching to trastuzumab alone. However, the trastuzumab plus letrozole combination was more effective than letrozole alone only in refractory breast tumors. These results suggested that blocking both ER and HER-2 signaling may delay the development of resistance to AIs in patients with recurrent breast cancer. Cancer 2008. © 2007 American Cancer Society.
A 60+ GHz packaged static divider implemented in InP DHBT technology

This paper presents a packaged 60+ GHz frequency divider implemented indium phosphide (InP) double-heterostructure bipolar transistor (DHBT) technology. The divider circuit chip was designed using a 135 GHz InP DHBT technology and demonstrated on wafer 100+ GHz toggling frequency. Measurements on the packaged divider showed a 60+ GHz toggle rate. To our knowledge, this is the highest toggling frequency reported on a packaged IC in any technology.
Impact of a First-Year Student Pharmacist Diabetes Self-Care Education Program

Objective. To evaluate the effectiveness of a first-year diabetes self-care education program by measuring student pharmacists’ confidence and knowledge retention, and the clinical applicability of the skills learned. Design. Integrated into a Pharmacy Practice Course, a 9-hour program consisting of lectures, a home glucose monitor assignment, and active-learning workshops was completed by 2 cohorts of first-year student pharmacists. Three survey instruments were developed and administered to the student pharmacists prior to the program, immediately after the program, and 9 months after the program to assess confidence, knowledge retention, and the clinical applicability of the knowledge and skills learned. Assessment. In cohort 1, 54 student pharmacists (response rate 90%) perceived that their confidence and ability improved significantly (increased by 88% and 110%, respectively, from baseline, p<0.001). Overall knowledge of diabetes increased as well as indicated by a 40% increase in test scores (p<0.001). About two-thirds of student pharmacists used their training to assist patients with diabetes within 9 months of completing the program. Findings in cohort 2 mirrored those observed with cohort 1, indicating good generalizability. Conclusions. An innovative first-year diabetes self-care education program significantly improved student pharmacists’ knowledge and confidence in providing diabetes self-care education, and the majority immediately used their leaned skills to assist diabetes patients and caregivers. Training first-year student pharmacists in diabetes care so they are prepared to use these skills as early as their first year of pharmacy school may be an effective approach to increasing the number of providers available to counsel and care for this expanding patient population.
Glucose control in severely thermally injured pediatric patients: What glucose range should be the target?

Hyperglycemia is a common pathophysiological phenomenon in burn and critically ill patients. During the early phases of postburn, hyperglycemia is due to an increased rate of glucose appearance along with an impaired tissue extraction of glucose leading to an increase of glucose and lactate1, 2 associated with impaired insulin receptor signaling and endoplasmic reticulum stress.3–5 The clinical relevance of hyperglycemia after a severe burn was shown in recent studies in which the authors showed that burn patients with poor glucose control had a significantly higher incidence of bacteremia/fungemia and mortality.6–8 These data indicate that hyperglycemia, associated with insulin resistance, represents a significant clinical problem in burn patients similar to insulin resistance in critically ill patients. Tight euglycemic control as published by van den Berghe and colleagues9 changed ICU practice. They showed that insulin administered to maintain glucose at levels below 110 mg/dl decreased morbidity and mortality in surgically critically ill patients and morbidity in medically critically ill patients.10 In another study, the authors showed that tight euglycemic control improved mortality in pediatric ICU patients11 and insulin given during the acute phase not only improved acute hospital outcomes but also improved long-term rehabilitation and social reintegration of critically ill patients over a period of 1 year12, 13, indicating the advantage of insulin therapy. Various unicenter and multicenter studies followed the Leuven trials to determine whether tight euglycemic control, in fact, improves outcomes of critically ill, septic, trauma, and medical patients. Results of these studies were mixed with some showing a benefit with the use of euglycemic control14, 15, while others failed to show improved outcomes; in contrast, some of these studies even demonstrated detrimental effects associated with tight euglycemic control and a dramatically increase in the incidence of hypoglycemia.16 A large multicenter trial was initiated: the NICE SUGAR trial, which failed to show beneficial outcome for critically ill patients with intensive insulin therapy17. This trial on the other hand delineated risks and problems associated with tight euglycemic therapy. Given all these controversial findings, current recommendations which glucose range should be targeted, are now based on opinions and not on scientific evidence. We, therefore, designed this trial in severely burned patients to answer the question which glucose levels are associated with improved morbidity and mortality. We hypothesized that hypoglycemia as well as hyperglycemia are detrimental for severely thermally injured patient outcome and that an ideal glucose range exists that is associated with improved morbidity and mortality.
Congestive heart failure and sleep apnoea-possible mechanisms and effect of CPAP therapy.

SUMMARY Sleep-disordered breathing has been associated with increased cardiovascular morbidity and mortality. However, despite several plausible mechanisms whereby obstructive sleep apnoea might be associated with left ventricular dysfunction and congestive heart failure, only limited data exist linking those disorders. These studies are reviewed along with possible mechanisms leading to left ventricular dysfunction in obstructive sleep apnoea. Recent investigations demonstrating improvement in left ventricular function after CPAP therapy in patients with congestive heart failure are reviewed as well. Finally, new data are presented from an animal model of congestive heart failure demonstrating a beneficial effect of CPAP on cardiac index in association with a decline in systematic vascular resistance. Remarkably, these effects persisted even after CPAP was removed. Possible mechanisms whereby CPAP may lead to improvement in cardiac output are discussed.
Spontaneous beat-to-beat variation of PR interval in normal children☆

Autonomic innervation of the heart both directly and indirectly influences conduction through the atrioventricular (AV) node.1–3 Sympathetic stimulation directly decreases cycle length by way of the sinoatrial node and enhances AV conduction through the AV node. Parasympathetic activity directly increases cycle length and prolongs AV conduction. However, changes in cycle length cause opposite changes in AV conduction time (indirect effect), thereby modulating direct effects of autonomic activity on AV conduction.1–3 This study non-invasively investigated the net influence of these opposing factors on AV conduction during spontaneous variation of cycle length.
Serum enzyme levels during exercise in patients with coronary heart disease: Effects of training

Abstract Arterial lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) levels were measured at rest and during exercise, before and after a conditioning program, in 11 patients with coronary artery disease. Myocardial A-V differences of LDH were also obtained during exercise in 5 patients. No significant elevation of the arterial myocardial LDH fraction (LDH-1) or of CPK was seen during exercise. In the untrained subjects, arterial LDH-5 concentration rose during exercise before training. This rise was attenuated by the training program. Myocardial production of LDH, its isoenzymes, or CPK was not found, even during exercise producing anginal pain. These data suggest that tolerable exercise does not cause significant myocardial injury. Evidence for a peripheral effect of conditioning is deduced from changes in LDH-5 response to exercise.
Functional Ability in Executive Variant Alzheimer's Disease and Typical Alzheimer's Disease

A frontal, or executive, variant of Alzheimer's disease (EAD) has been described in the literature in which frontal dysfunction accompanies temporal and parietal changes in the early stages of the illness. However, no study has empirically investigated associated aspects, such as neuropsychiatric symptoms, instrumental activities of daily living, or caregiver burden in this EAD subgroup. We compared the performance of two subgroups of mild Alzheimer's disease patients (e.g., EAD and typical Alzheimer's disease; TAD) on neuropsychological and associated measures. Results revealed that the EAD group, selected based on poor executive scores, did not significantly differ from the TAD group on nonexecutive neuropsychological tests of intelligence, language, verbal and nonverbal memory, or visual-spatial abilities. However, the EAD group evidenced more severe neuropsychiatric symptoms, impaired activities of daily living, and greater caregiver distress than the TAD group. Thus, the EAD subgroup is characterized...
Food deprivation and cocaine self-administration.

Abstract The effects of food deprivation on the self-administration of cocaine were assessed in three rhesus monkeys under different schedules of reinforcement. In one subject, decreasing body weight to 80% of free-feeding weight (ffw) resulted in increased response rates and number of cocaine infusions taken. The same effects were observed in a second subject when restricted food intake resulted in 88% ffw. When schedule contingencies limited the number of infusions available, reduction to 90% ffw in the third subject resulted in increased response rates. These data suggest that food deprivation can be a potent variable in responding maintained by cocaine self-administration.
PRIVATE EQUITY INVESTING IN EMERGING MARKETS

After a proliferation of emerging market funds in the 1990s, growth has slowed drastically due to disappointing preliminary results. Private sector funds initially appeared promising because of the burgeoning demand for capital in emerging markets, the new receptivity of governments to foreign investors, and the prospect of high returns. But in many cases, the regulatory and legal frameworks did not provide adequate investor protection, and dramatic differences in accounting standards, corporate governance, and exit potential created problems. These problems are often accentuated because local owners are adept at navigating the legal and accounting systems, placing investors at a disadvantage. As global competition intensifies, local policies, regulations, and business practices are becoming increasingly important in attracting investors. Local governments must institute the reforms necessary to improve the investment environment, including the strengthening of shareholder rights and corporate governance standards and improving access to public equity markets. Development finance institutions must provide direction and leadership in these areas. And fund managers must align their business models more closely with emerging market realities by establishing a local presence, adopting a more hands-on approach to monitoring their investments, and developing creative exit strategies.
Financing Capacity in the Bottleneck Model

Abstract It is well known that, for a congestible facility with constant long-run average cost, the revenue from the unconstrained optimal congestion charge (set so that each individual faces the marginal (social) cost of a use) exactly covers the cost of optimal capacity. In the context of Vickrey′s bottleneck model of morning rush-hour auto congestion, this paper investigates under what circumstances the first-best pricing and investment rules apply when both the time variation of the congestion charge is constrained and users differ in unobservable characteristics so that the same congestion charge must be applied to heterogeneous users.
Characterization of human cells: Variation in growth rate, volume, morphology and growth efficiency in media supplemented with human serum or bovine fetal serum

Abstract Three cell strains in process of cultural establishment were characterized during serial passage by large inocula. The cell lines, shown poliovirus-susceptible, were received as derived from human fetal small intestine and collagenase-treated or plasma-clot-explanted human adult lung carcinoma, after 6, 27 and 27 passages respectively. Cultures were passed in medium supplemented with human adult serum or bovine fetal serum, and at each serial passage were grown also in medium supplemented with both sera. After four serial passages, effects of different basal medium and serum on growth of the separated sublines was tested. Sublines were compared by examination of colony morphology, cell yield, cell-volume distribution, single-colony growth and cell chromosome number. Influence of cultural conditions was reflected quantitatively rather than qualitatively by effects on cell properties, except that growth of one strain was not enhanced by bovine fetal serum in medium. Growth of sublines in single-serum medium did not enhance capacity for growth in that medium selectively. Similar response was shown by two sublines selected in human-serum medium by colony-to-colony passage. These studies showed that cellular properties as exhibited by these cultures could be affected variously by cultural conditions, and that multiple criteria were needed for differential characterization.
Participatory ergonomics: Development of an employee assessment questionnaire ☆

Abstract Despite being essential to the success of participatory ergonomics (PEs) programs, there are currently no known quantitative measures that capture the employees’ perspective of PE program effectiveness. The present study addresses this need through the development of the Employee Perceptions of Participatory Ergonomics Questionnaire (EPPEQ). The questionnaire is designed to assess five key components that are based on a review of the available literature: Employee Involvement , Knowledge Base , Managerial Support , Employee Support , and Strain related to ergonomic changes . In Phase 1, a sample of employees and ergonomists working at a manufacturing plant was used to develop and test an initial set of items. In Phase 2, data was collected from a nation-wide sample of employees representing a wide range of jobs and organizations to cross-validate the results from Phase 1. Phase 2 results indicate that the five EPPEQ subscales demonstrate sound convergent validity and are also correlated with traditional indicators of PE program success. Implications and uses of the EPPEQ are discussed.
On the iron oxide neutral cluster distribution in the gas phase. II. Detection through 118 nm single photon ionization.

Iron oxide (FemOn) neutral clusters are generated in the gas phase through laser ablation of the metal and reaction with various concentrations of O2 in He. The mixture of expansion gas and neutral FemOn cluster species is expanded through a supersonic nozzle into a vacuum system, in which the clusters are ionized by an ArF excimer laser at 193 nm, and the ions are detected and identified in a time-of-flight mass spectrometer. In this report, the experimental parameters that influence the observed cluster distributions, such as ablation laser power, expansion pressure, vacuum system pressure, and 193 nm ArF ionization laser power, are explored. In the second paper in this series, the effect of the ionization laser wavelength (355 nm, 193 nm, 118 nm) on the observed cluster ion distribution is explored. The cluster ion distribution observed employing 193 nm laser ionization, is sensitive to the neutral cluster distribution as evidenced by the change in the observed time-of-flight mass spectra with changes in laser power, growth conditions, and expansion conditions. The thermodynamically stable neutral clusters for saturated O2 growth conditions are suggested to be of the forms FemOm, FemO(m+1), and FemO(m+2); which one of these series of neutral clusters is most stable depends on the size of the cluster. For m < 10, FemOm is the most stable neutral cluster series, for 10 < or = m < or = 20, FemO(m+1) is the most stable neutral cluster series, and for 21 < or = m < = 30, FemO(m+2) is the most stable neutral cluster series. Some neutral cluster fragmentation is clearly present for 193 nm ionization due to multiphoton absorption in both the neutral and ionic cluster species.
Identification of a Ligand-Binding Region of the Human Insulin Receptor Encoded by the Second Exon of the Gene

Structure-function studies of the insulin molecule indicate that an insulin B chain domain comprising residues 22–26 is involved both in binding to the insulin receptor (INSR) and in insulin dimer formation, suggesting that this domain might also interact with a structure resembling the insulin dimer interface in the INSR. Expression of a mutant INSR cDNA with a deletion of the region corresponding to exon 2 of the INSR gene produces a protein devoid of insulin-binding activity, although the mutant protein is processed appropriately to α- and β-subunits, suggesting that the insulin-binding domain is encoded at least in part by exon 2. Within this region of the INSR molecule, the sequence 83–103 fulfills the structural criteria for a dimer interface. Studies of mutant INSRs with substitutions for phenylalanine 88 or 89 show that the presence of phenylalanine at position 89 is essential for full binding affinity.
Prethrombolytic versus thrombolytic era risk stratification of patients with acute myocardial infarction.

Abstract In conclusion, predictors of short-term mortality for patients with acute myocardial infarction have not changed with the advent of the thrombolytic era. Two criteria based on age, diabetes, and number of leads with ST elevation suggest which patients are at highest risk and may warrant further consideration for either additional or alternate therapy.
Effects of oxygen at high concentrations and food deprivation on cell division in lung alveoli of mice.

Abstract Cell division is inhibited by exposure of mice to high oxygen (O 2 ). Because the exposed animals consume less food, relative to controls, a question arose about the effect of food deprivation per se on cell division. The purpose of this project was to compare the cell division in lung alveoli of animals: breathing air (A), exposed to high O 2 (O), deprived of food (D), and exposed to high O 2 plus deprived of food (OD). Swiss-Webster mice were divided into four equal groups: A, O, D, and OD. Animals from each group were sacrificed daily from 0–5 days. Cells synthesizing DNA and preparing to divide were labeled with tritiated thymidine. Labeled cells were visualized with autoradiography, counted with the light microscope, and expressed as a labeling index. Groups O and D showed statistically similar progressive decreases in cell labeling. Regression analysis testing for differences in trends showed that the combined data from groups O and D differed significantly from both the group A cell labeling, which did not decrease over 5 days, and the group OD cell labeling, which decreased dramatically. Generally similar results were found for body weight changes in the respective groups. These results show that: (1) Complete food deprivation with weight loss causes a decrease in the number of cells synthesizing DNA; (2) exposure to high O 2 causes a decrease in DNA synthesis, similar to that seen with food-deprivation weight loss; (3) exposure to high O 2 results in a decreased food intake and produces about the same weight loss as complete food deprivation; and (4) complete food deprivation of high-O 2 -exposed mice produces more weight loss and decreases DNA synthesis even more. Thus, to the extent that it occurs, the decreased-food-associated weight loss during exposure to high O 2 is a principal factor in decreasing DNA synthesis.
Shock induced multi-mode damage in depleted Uranium

Recent dynamic damage studies on depleted uranium samples have revealed mixed mode failure mechanisms leading to incipient cracking as well as ductile failure processes. Results show that delamination of inclusions upon compression may provide nucleation sites for damage initiation in the form of crack tip production. However, under tension the material propagates cracks in a mixed shear localization and mode-I ductile tearing and cracking. Cracks tips appear to link up through regions of severe, shear dominated plastic flow. Shock recovery experiments were conducted on a 50 mm single stage light gas gun. Serial metallographic sectioning was conducted on the recovered samples to characterize the bulk response of the sample. Experiments show delaminated inclusions due to uniaxial compression without damage propagation. Further results show the propagation of the damage through tensile loading to the incipient state, illustrating ductile processes coupled with mixed mode-I tensile ductile tearing, shear localization, and mode-I cracking in depleted uranium.
An Empirical Comparison of Methods for Eliciting and Modeling Expert Knowledge

The goal of this project in Human-Centered Computing was to apply a variety of methods of Cognitive Task Analysis (CTA) and Cognitive Field Research (CFR) to support a complete process going all the way from knowledge elicitation to leverage point identification and then to system prototyping, and also use this as an opportunity to empirically compare and evaluate the methods. The research relied upon the participation of expert, journeyman, and apprentice weather forecasters at the Naval Training Meteorology and Oceanography Facility at Pensacola Naval Air Station. Methods included Protocol Analysis, a number of types of structured interviews, workspace and work patterns analysis, the Critical Decision Method, the Knowledge Audit, Concept Mapping, and the Cognitive Modeling Procedure. The methods were compared in terms of (1) their yield of information that was useful in modeling expert knowledge, (2) their yield in terms of identification of leverage points (where the application of new technology might...
Syncope and Sudden Death in the Athlete

Sudden unexpected death in an athlete is a rare but devastating event. When it occurs, it has a lasting and serious impact on the family, the school, and the community in which the athlete lived. This article will examine the epidemiology of sudden unexpected death in children and adolescents as well as explore the etiologies most commonly encountered. Syncope in an athlete is equally as frightening and may be an early indicator of a possible fatal event if not fully evaluated. The preparticipation physical examination is one possible tool that may decrease the frequency of these untimely events. The association between syncope, the preparticipation examination, and sudden unexpected death in the athlete will be explored.
Potential for Use of All-MOX Fuel in Existing and Evolutionary/Advanced LWRS in the United States

Disposition of excess weapon plutonium following the end of the cold war and execution of the strategic arms reduction treaties between the United States and Russia has been a topic of great interest in the United States for some time. At Lawrence Livermore National Laboratory, we began to study methods for disposing of not only plutonium but highly enriched uranium late in 1991. Activities in this area were stimulated by a session [1] chaired by Dr. William Sutcliffe at the annual meeting of the American Association for the Advancement of Science (AAAS) in February 1991.
Mathematical modelling of objectives in radiation therapy treatment planning.

The authors view radiation therapy treatment planning (RTTP) as a problem of constrained optimization. In this context, the 'optimal' treatment is one that maximizes some objective function subject to the inherent constraints of the problem. They discuss two objective functions which are motivated by biological considerations rather than mathematical expedience. One of these measures the 'goodness' of a treatment in terms of its probability of success. The other measures the degree to which a treatment succeeds in satisfying a system of constraints that are mutually contradictory. The authors describe how to actually perform the optimization of these objective functions in practice and show some numerical results which demonstrate advantages of these objective functions over their more conventional counterparts.
A Coordinated Approach to Improving Outcomes for Substance‐Abusing Families in Juvenile Dependency Court

This paper describes a coordinated approach to providing enhanced services for substance-abusing families in the juvenile dependency court. The enhanced services consisted of an interagency collaborative model including the Department of Social Services, Court Appointed Special Advocates, Public Health Nurses, and Family Support Specialists. The purpose of the intervention was to increase the likelihood of family reunification. Families were randomly assigned to either the enhanced services (N=48) or to a regular services group (N=41). Variables included social background factors, data related to court hearings and court orders, and final court outcomes regarding placement and custody. Significant factors predicting final placement of the child were completion of court ordered programs, a stable home, and mothers' cooperation and motivation. Families who received the enhanced services had significantly higher rates of reunification of children with parents.
New Directions in Pain Research: Molecules to Maladies

Neuropathic pain follows injury or disease of the nervous system, most commonly of peripheral nerves. It is often severe and intractable and may not respond even to powerful opiates. As such, it constitutes a major frontier for pain research. Peripheral nerve injury leads to the appearance of ectopic impulse discharge in large- and small-diameter primary afferent neurons (Amir and Devor 1997xSpike-evoked suppression and burst patterning in dorsal root ganglion neurons of the rat. Amir, R and Devor, M. J. Physiol. (Lond.). 1997; 501: 183–196Crossref | Scopus (50)See all ReferencesAmir and Devor 1997). The resulting hyperexcitability yields not only spontaneous ectopic discharge but also hypersensitivity to a broad range of stimuli, including mechanical displacement and noradrenaline released by sympathetic efferent activity (sympathetically maintained pain) (McLachlan et al. 1993xPeripheral nerve injury triggers noradrenergic sprouting within dorsal root ganglia. McLachlan, E.M, Janig, W, Devor, M, and Michaelis, M. Nature. 1993; 363: 543Crossref | PubMed | Scopus (508)See all ReferencesMcLachlan et al. 1993). Musculoskeletal and visceral pain states are characterized by hyperalgesia (tenderness). In contrast to nociceptors in the cutaneous and musculoskeletal systems, visceral nociceptors are quiescent and relatively insensitive to mechanical stimuli unless the tissue is inflamed (Cervero and Janig 1992xVisceral nociceptors (a new world order?) . Cervero, F and Janig, W. Trends Neurosci. 1992; 15: 374–378Abstract | Full Text PDF | PubMed | Scopus (139)See all ReferencesCervero and Janig 1992), whereupon they undergo phenotypic changes.In conclusion, the participants at the workshop provided an exciting view of a rapidly advancing field of research. More than a half century after Sherrington introduced the term “nociceptor” into the scientific literature and over a quarter century after Melzack and Wall gave us the Gate-Control Theory of pain, modern experimental methods have transformed the field, carrying it beyond the issues of neural specificity and patterning, allowing us to answer questions with greater precision and certainty. The major focus of this meeting was the primary afferent nociceptor, which we have learned is remarkably plastic in its response to stimuli. How primary afferent activity actually produces pain, however, particularly in the setting of injury, involves complex interactions at the level of the spinal cord and brain. Many of the models and techniques presented at this conference have great potential to promote a cohesive understanding of how the pain experience arises, how it is modulated within the nervous system, and ultimately how it may be successfully treated.
Prioritizing the transformative value of biodiversity

Hopefully this is the first of many such books: a biologically informed examination of the ethical and epistemological issues arising from considerations about how and why we should conserve biodiversity. In a nutshell, Sarkar develops Bryan Norton’s concept of ‘‘transformative value’’ to justify why we should conserve biodiversity and uses insight from the developing field of Conservation Biology, notably ‘‘place prioritization’’ algorithms and ‘‘multiple criterion synchronization’’ (MCS) to guide how we should conserve biodiversity (Norton 1987). He focuses more on the how than the why and the heart of the book is an examination of the foundations of Conservation Biology.
Optimism and consistency in partitioned distributed database systems

A protocol for transaction processing during partition failures is presented which guarantees mutual consistency between copies of data-items after repair is completed. The protocol is “optimistic” in that transactions are processed without restrictions during failure; conflicts are then detected at repair time using a precedence graph, and are resolved by backing out transactions according to some backout strategy. The resulting database state then corresponds to a serial execution of some subset of transactions run during the failure. Results from simulation and probabilistic modeling show that the optimistic protocol is a reasonable alternative in many cases. Conditions under which the protocol performs well are noted, and suggestions are made as to how performance can be improved. In particular, a backout strategy is presented which takes into account individual transaction costs and attempts to minimize total backout cost. Although the problem of choosing transactions to minimize total backout cost is, in general, NP-complete, the backout strategy is efficient and produces very good results.
Hunter and Nonhunter Beliefs about Chronic Wasting Disease in Wisconsin

We examined beliefs of landowners who hunt and do not hunt regarding chronic wasting disease (CWD) and its management. We mailed surveys to a random sample of 973 Wisconsin, USA, landowners living in the CWD southwest disease eradication zone. Of 613 respondents, 360 (59%) were hunters and 253 (41%) were not hunters. We created multiple item indices to measure respondent beliefs about effects of CWD and its management. Hunters and nonhunters differed on 5 of 6 belief indices. Both groups were, on average, relatively neutral in their trust of the Wisconsin Department of Natural Resources but landowners who did not hunt reported slightly higher trust. Both groups were neutral or slightly agreed that CWD should be managed and they were concerned about deer (Odocoileus spp.) health and the safety of eating venison. Landowners who did not hunt were more likely than those who hunted to agree with these issues but effect sizes indicated these differences were minimal. Landowners who hunted were more concerned than nonhunters about effects of CWD on deer hunting. Cluster analyses indicated most nonhunting landowners were neutral or not concerned about CWD and its management, whereas most hunting landowners were concerned. Our results suggest that managers should use communication campaigns to increase awareness and mitigate concerns about CWD, increase trust and input related to the disease, and inform publics about CWD management strategies.
Polymorphism of methylchloromethane compounds. IX: A low-temperature X-ray diffraction study of the orientationally disordered phases of t-butyl bromide and their relationship to the methylchloromethane compounds

Abstract A single-crystal X-ray diffraction study has shown that t-butyl bromide forms an orientationally disordered phase, with a face-centered cubic unit cell (a=8.77(1) A ), when it is cooled from the melt. As it is cooled further, it undergoes a reversible transition to an optically anisotropic orientationally disordered rhombohedral phase, with a=15.087(13) A and α=89.17(7)°. The dimensions and the intensity distribution of this phase are similar to those found in the rhombohedral phases of certain other pseudo-spherical molecules. The literature covering the solid phases of t-butyl bromide has been reviewed and some previously reported results have been re-interpreted in light of the identification of this rhombohedral phase. In addition, unit-cell dimensions for the rhombohedral phases of carbon tetrachloride and 2,2-dichloropropane were re-measured using single crystals. They are a=14.47(3) A , α=89.63(16)° and a=14.565(14) A , α=89.33(8)°, respectively.
DNA excision repair as a component of adaptation to low doses of ionizing radiation Escherichia coli

In this study we examined whether or not DNA excision repair is a component of adaptation induced by very low-dose ionizing radiation in Escherichia coli, a well-characterized prokaryote, and investigated the relationship between enhanced excision repair and the SOS response. Competent E. coli cells were irradiated using low doses (0·1–10 Gy) of 137Cs γ-rays, allowed to recover for 2 h and were then transformed using pUC18 DNA containing approximately 22 oxidized thymine residues (thymine glycols) per molecule. Successful transformants were identified by recovery of plasmid-borne ampicillin resistance and the resulting data (colony counts) were used to calculate ratios of plasmid recovery in irradiated to control cells. Results showed that cells irradiated with very low doses (0·1–0·5 Gy) were up to 30–40% more efficient at utilizing thymine glycol-containing pUC18 DNA. The enhanced excision repair by very low doses (< 0·5 Gy) of γ-rays was shown to be independent of the recA-controlled SOS response in ex...
On the vibration of a visco-elastic cylindrical shell and a composite visco-elastic cylinder with an isotropic core in an axial magnetic field

The electrc-magnetic equations of Maxwell and the equations of mechanical motion have been used to investigate the vibrations of a cylindrical shell and also a cylinder with an isotropic core characterised by a visco-elasticity of Voigt tupe.
Fusion of bacterial spheroplasts by electric fields.

Spheroplasts of Escherichia coli or Salmonella typhimurium were found to fuse in an electric field. We employed the fusion method developed by Zimmermann and Scheurich (1981): Close membrane contact between cells is established by dielectrophoresis (formation of chains of cells by an a.c. field), then membrane fusion is induced by the application of short pulses of direct current. Under optimum conditions the fusion yield was routinely 90%. Fusable spheroplasts were obtained by first growing filamentous bacteria in the presence of cephalexin, then converting these to spheroplasts by the use of lysozyme. The fusion products were viable and regenerated to the regular bacterial form. Fusion of genetically different spheroplasts resulted in strains of bacteria possessing a combination of genetic markers. Fusion could not be achieved with spheroplasts obtained by growing the cells in the presence of penicillin or by using lysozyme on bacteria of usual size.
Distributed, anytime optimization in power-generator networks for economic dispatch

This paper considers the economic dispatch problem for a group of power generating units communicating over an arbitrary strongly connected, weight-balanced digraph. The goal of the group is to collectively meet a specified load while respecting individual generation bounds and minimizing the total generation cost, which corresponds to the sum of individual arbitrary convex functions. We introduce a distributed coordination algorithm, termed Laplacian-set-valued dynamics, and establish its asymptotic convergence to the solutions of the economic dispatch problem. In addition, we show that the algorithm is anytime, meaning that its executions are feasible solutions at all times and the total cost monotonically decreases as time elapses. The technical approach combines notions and tools from algebraic graph theory, nonsmooth analysis, set-valued dynamical systems, and penalty functions. Several simulations illustrate our results.
Penetration and Overshooting in Turbulent Compressible Convection

We present the results of a series of high-resolution, three-dimensional numerical experiments that investigate the nature of turbulent compressible convective motions extending from a convection zone into a stable layer below. In such convection, converging flows in the near-surface cellular convecting network create strong downflowing plumes that can traverse the multiple scale heights of the convection zone. Such structures can continue their downward motions beyond the convecting region, piercing the stable layer, where they are decelerated by buoyancy braking. If these motions mix entropy to an adiabatic state below the convection zone, the process is known as penetration; otherwise it is termed overshooting. We find that in threedimensional turbulent compressible convection at the parameters studied, motions generally overshoot a significant fraction of the local pressure scale height but do not establish an adiabatic penetrative region, even at
Different hepatocytes express the cholesterol 7α‐hydroxylase gene during its circadian modulation in vivo

Cholesterol 7α-hydroxylase, the rate-limiting enzyme in bile salt synthesis from cholesterol is a P450 enzyme (CYP7A). Its expression and activity are regulated by bile salts, cholesterol, hormones and a circadian modulator. Here we define the hepatocytes contributing to the expression of the rat CYP7A gene during its in vivo circadian variation. The diurnal expression of the CYP7A messenger RNA (mRNA) was studied by in situ hybridization and correlated with the diurnal rate of CYP7A gene transcription and mRNA expression. At 10 AM, the time of lowest mRNA expression and gene transcription rate, only four to five hepatocytes, located close to the hepatic venules (“perivenular”), contained the CYP7A mRNA. At 10 PM, the time of highest mRNA expression and fastest in vitro transcription rate, approximately one half of the hepatocytes (still in a “perivenular” location) contained the cholesterol 7α-hydroxylase mRNA. In addition, the measured half-life of the CYP7A mRNA was shorter at 10 AM than at 10 PM suggesting that posttranscriptional mechanisms also contributed to the observed circadian differences. Therefore, the basal transcription rate of the CYP7A gene is maintained by four to five “perivenular” hepatocytes. During the circadian variation, the rate of gene transcription increases in these “perivenular” hepatocytes, but in addition, there is recruitment of other more proximal hepatocytes to transcribe the gene. It is proposed here that the response of specific hepatocytes to the various modulators of CYP7A gene expression is dependent on the relative position of these hepatocytes within the liver cell plate.
P5-S1.02 Sexual risk behaviours and mental health concerns among HIV-infected MSM

Background Some HIV-infected MSM are at risk for acquisition and transmission of STDs because of ongoing high risk sexual behaviours. HIV-infected MSM also can experience psychosocial stressors and related mental health issues. We assessed the association between STD risk behaviours and the desire to discuss mental health issues, as reported by HIV-infected MSM currently receiving care in HIV clinics. Methods In 2007, 426 HIV-infected MSM receiving care in eight urban HIV clinics were randomly selected to complete a survey that queried them about risk behaviours and health concerns. We estimated the percentages who answered that they wanted to discuss their mental health with their clinicians, by sexual behaviour and substance use in the past year. Differences in percentages of patients were considered statistically significant if the two tailed p value was ≤0.05 using a χ 2 test. Results 90% of patients had initiated care for their HIV infection more than a year ago. In the year preceding the survey, 74% had multiple sexual partners, 75% engaged in anal intercourse, 48% had at least one HIV-uninfected partner, and 82% used illegal psychoactive drugs. Among those who reported anal intercourse, 39% did not use a condom during the most recent episode. Among patients, 70% wanted to talk with their clinicians about how they felt mentally or emotionally. Patients who engaged in unprotected receptive anal sex were more likely to want such a conversation than those who did not engage in unprotected receptive anal sex (80% vs 62%, p Conclusions Although the vast majority of these patients had been in treatment for more than a year, a large percentage of patients engaged in substance abuse and sexual behaviours that increase their risk of HIV transmission, and STD transmission and acquisition. Such patients were more likely to want to discuss their mental health concerns than those who did not engage in these behaviours. These findings underscore the importance of interventions to decrease risky sexual behaviour and to promote clinical assessment of mental health needs for this patient population. A mental health assessment can identify patients who might need greater psychosocial support or referral for treatment of substance abuse and underlying mental illness.
Inhibition of CtBP1 activity by Akt-mediated phosphorylation

Pc2 (Cbx4) is a member of the chromobox family of polycomb proteins, and is a SUMO E3 ligase for the transcriptional corepressor CtBP1. Here, we show that both CtBP1 and Pc2 are phosphorylated by the kinase Akt1, which is activated by growth factor signaling via the PI3-kinase pathway. In the presence of Pc2, phosphorylation of CtBP1 is increased, and this requires interaction of both CtBP1 and Akt1 with Pc2. Pc2 promotes CtBP1 phosphorylation by recruiting Akt1 and, in part, by preventing de-phosphorylation of activated Akt1. Alteration of the Akt-phosphorylated residue in CtBP1 to a phosphomimetic results in decreased CtBP1 dimerization, but does not prevent interaction with other transcriptional regulators. The phosphomimetic mutant of CtBP1 is expressed at a lower level than the wild type protein, resulting in decreased transcriptional repression. We show that this CtBP1 mutant is targeted for poly-ubiquitylation and is less stable than the wild type protein. Co-expression of Pc2 and Akt1 results in both phosphorylation and ubiquitylation of CtBP1, thereby targeting CtBP1 for degradation. This work suggests that Pc2 might coordinate multiple enzymatic activities to regulate CtBP1 function.
BEHAB/brevican: a brain-specific lectican implicated in gliomas and glial cell motility

Several recent findings have advanced our understanding of the composition and function of the brain extracellular matrix (ECM). BEHAB/brevican, a recently identified CNS-specific proteoglycan, is a component of the brain ECM and is upregulated during glial cell motility. It is expressed at high levels during development, in response to injury, and in primary brain tumors. Cleavage of the BEHAB/brevican protein may increase invasion of tumor cells.
An assessment of some hazards associated with the collection of venous blood

Some potential hazards of three commercially available blood collecting devices are compared with the conventional syringe method. A simulated venous system using blood containing a bacterial spore tracer was used to estimate surface and aerosol contamination. No appreciable difference in potential hazard to the operator was demonstrable by the methods employed.
Enzyme-activated, Hypoxia-Selective DNA Damage by 3-amino-2-quinoxalinecarbonitrile 1,4-di-N-oxide

The compound 3-amino-2-quinoxalinecarbonitrile 1,4-dioxide (4) displays potent hypoxia-selective cytotoxicity in cell culture. This compound is structurally similar to the known hypoxia-selective DNA-damaging agent tirapazamine (1, TPZ), but the ability of 4 to cause DNA damage under low-oxygen conditions has not previously been characterized. The results presented here provide the first evidence that 4 causes reductively activated DNA damage under hypoxic conditions. The findings indicate that one-electron reduction of 4 by NADPH:cytochrome P450 reductase yields an oxygen-sensitive intermediate (5). This activated intermediate is rapidly destroyed by reaction with O2 under aerobic conditions, but goes forward to cause DNA damage under low-oxygen conditions. Analysis of the DNA damage indicates that reductive activation of 4 leads to production of a highly reactive, freely diffusible oxidizing radical that causes sequence-independent cleavage of the deoxyribose backbone and oxidative damage to the heteroc...