cssi/SciSciGPT-SciSciNet huggingface dataset:
Impact of Sirococcus shoot blight (Sirococcus tsugae) and other damaging agents on eastern hemlock (Tsuga canadensis) regeneration in Northeastern USA

Abstract In 2009, Sirococcus tsugae was first reported in Maine on eastern hemlock. Our goal was to quantify the impact of the shoot blight disease caused by this fungal pathogen of unknown origin on eastern hemlock regeneration. From 2013 to 2014, 59 long-term monitoring plots established by the US Forest Service (USFS) Forest Inventory and Analysis (FIA) program in New England and New York were surveyed to determine the impact of S. tsugae. Damage by hemlock woolly adelgid (Adelges tsugae), elongate hemlock scale (Fiorinia externa), white-tailed deer (Odocoileus virginianus), or other causes was also recorded. Disease incidence and severity (percentage of shoots blighted and percentage of crown defoliated) were assessed for 20 seedlings per plot. Sirococcus shoot blight symptoms were present in most plots (90%) and on most seedlings (72%). For the majority of seedlings, blight affected less than 10% of shoots, but the percentage of shoots blighted did range up to 75%. Similarly, needle loss was limited to less than 25% of the crown for most seedlings. Disease severity was positively correlated with overstory hemlock density. Using species-specific polymerase chain reaction (PCR) primers, Sirococcus tsugae was identified from samples collected in the majority of sites (68%) in New England and New York. In permanent plots at the Massabesic Experimental Forest in Maine, disease symptom severity increased from 16% blighted shoots in 2011 to 47% blighted shoots in 2013. Results confirm that Sirococcus shoot blight of eastern hemlock is more widespread in natural forests of northeastern USA than previously known and that symptoms can be severe (>75% blighted shoots) in some locations.
A response to Chisholm’s paradox

Essentialists suppose that for every individual, if that individual exists at any possible world, then necessarily that individual exemplifies some non-trivial qualitative property essential to it, as such. Anti-essentialists deny this. One important argument leveled by some anti-essentialists against essentialism takes the form of a thought experiment, one originally introduced by Chisholm (Nous 1(1):1–8, 1967), sometimes referred to as Chisholm’s Paradox (CP). In this essay, I defend essentialism against CP. I begin by presenting the argument and showing how it leads to a contradiction of the essentialist thesis. I then consider one of the most popular solutions to CP to date, that given by Salmon (Midwest Stud Philos 11:75–120, 1986, Philos Rev 98(1):3–34, 1989, Philos Top 21(2):187–197, 1993). Next, I critique Salmon’s proposal and show that it is an insufficient response on behalf of the essentialist. And finally, I propose a novel solution to the paradox and discuss why it is that many metaphysicians in the past have found CP plausible, despite being fallacious.
Untangling Differences in Quality of Care in Medicare Advantage Versus Traditional Medicare Programs

Panagiotou and colleagues investigated whether enrollees hospitalized for heart failure, pneumonia, or acute myocardial infarction had lower readmission rates than those in traditional Medicare. Th...
The Twenty-Second Chapter

Still doth this chapter following (which is the last of this revelation) prosecute the spiritual and heavenly commodities of this city, concluding with most excellent admonitions and godly warnings.
Harnessing the anti-inflammatory properties of stem cells for transplant therapy in hemorrhagic stroke

Hemorrhagic stroke is a global health crisis plagued by neuroinflammation in the acute and chronic phases. Neuroinflammation approximates secondary cell death, which in turn robustly contributes to stroke pathology. Both the physiological and behavioral symptoms of stroke correlate with various inflammatory responses in animal and human studies. That slowing the secondary cell death mediated by this inflammation may attenuate stroke pathology presents a novel treatment strategy. To this end, experimental therapies employing stem cell transplants support their potential for neuroprotection and neuroregeneration after hemorrhagic stroke. In this review, we evaluate experiments using different types of stem cell transplants as treatments for stroke-induced neuroinflammation. We also update this emerging area by examining recent preclinical and clinical trials that have deployed these therapies. While further investigations are warranted to solidify their therapeutic profile, the reviewed studies largely posit stem cells as safe and potent biologics for stroke, specifically owing to their mode of action for sequestering neuroinflammation and promoting neuroregenerative processes.
Cinema as a form of listening: American music documentary: five case studies of ciné-ethnomusicology, by Benjamin H. Harbert, Middletown, CT, Wesleyan University Press, 2019, 302 pp., $27.95 (paperback), ISBN-13: 9780819578013

There are moments in Benjamin H. Harbert’s compelling book American Music Documentary: Five Case Studies of Cine-Ethnomusicology when it appears as if Harbert is writing to readers unfamiliar with ...
Oral Cytokine Levels Are More Linked to Levels of Plasma and Oral HIV-1 RNA Than to CD4+ T-Cell Counts in People With HIV

Author(s): Rocco, Joseph M; York, Zachary; Shen, Chengli; Shiboski, Caroline; Cyriaque-Webster, Jennifer; McLaughlin, Janet; Borowski, Luann; Chen, Huichao; Aberg, Judith A; Dittmer, Dirk P; Ghannoum, Mahmoud; Rinaldo, Charles R; Macatangay, Bernard | Abstract: BackgroundWe determined the levels of 11 soluble immune mediators in oral washings of AIDS Clinical Trials Group A5254 participants with varying degrees of plasma viremia and CD4 T-cell counts to characterize the mucosal immune response at different stages of HIV-1 infection.MethodsA5254 was a multicenter, cross-sectional study in people with HIV (PWH) recruited into 4 strata based on CD4 count and levels of plasma viremia: stratum (St) A: CD4 ≤200 cells/mm3, HIV-1 RNA (viral load [VL]) g1000 cps/mL; St B: CD4 ≤200, VL ≤1000; St C: CD4 g200, VL g1000; St D: CD4 g200, VL ≤1000. Oral/throat washings were obtained from all participants. Soluble markers were tested in oral/throat washings using a multibead fluorescent platform and were compared across strata. Linear regression was used to determine the associations between cytokines and HIV-1 in plasma and oral fluid.ResultsSt A participants had higher levels of interleukin (IL)-1β, IL-6, IL-17, tumor necrosis factor alpha (TNFα), and interferon gamma (IFNγ) compared with St B and D (P = .02; P l .0001) but were not different from St C. IL-8, IL-10, and IL-12 were elevated in St A compared with the other 3 strata (P = .046; P l .0001). Linear regression demonstrated that oral HIV-1 levels were associated with IL-1β, IL-6, IL-8, and TNFα production (R g .40; P l .001) when controlling for CD4 count and opportunistic infections.ConclusionsOur results show that high levels of oral HIV-1, rather than low CD4 counts, were linked to the production of oral immune mediators. Participants with AIDS and uncontrolled viremia demonstrated higher levels of pro- and anti-inflammatory soluble immune mediators compared with participants with lower HIV-1 RNA. The interplay of HIV-1 and these immune mediators could be important in the oral health of PWH.
The History and Evolution of Elbow Medial Ulnar Collateral Ligament Reconstruction: from Tommy John to 2020

The purpose of this review article is to discuss the evolution of surgical reconstruction of the anterior bundle of the UCL, otherwise known as Tommy John surgery, from Dr. Jobe’s initial description in 1986 to present day. In particular, the unique changes brought forth by each new surgical technique, and the reasons that these changes were implemented, are highlighted. The incidence of UCL reconstruction surgery continues to increase significantly, particularly in the 15- to 19-year-old age group. New anatomic understanding of the anterior bundle of the UCL, including the importance of the central fibers and the broad and tapered ulnar insertion, may affect optimal UCL reconstruction techniques in the future. Although return to play rates are generally quite high (80–95%), the mean time to return to play (typically 12–18 months for pitchers) is longer than desired. Accordingly, many authors feel that there remains room for improvement in the treatment of this common injury. The Tommy John surgery has evolved in many ways with the development of novel techniques over the last 35 years. Currently, overhead throwing athletes undergoing UCL reconstruction have high return to play and low complication rates. Future modifications to the surgery may aim to further improve outcomes and, more importantly, expedite the length of postoperative rehabilitation.
On the Dopability of Semiconductors and Governing Material Properties

To be practical, semiconductors need to be doped. Sometimes, they need to be doped to nearly degenerate levels, e.g., in applications such as thermoelectric, transparent electronics, or power elect...
Ovarian Cancer Survival in Missouri, 1996-2014.

Yilin Yoshida, PhD, MPH, (above), Chester L. Schmaltz, PhD, and Jeanette Jackson-Thompson, PhD, MSPH are in the University of Missouri School of Medicine, Department of Health Management and Informatics, and the Missouri Cancer Registry and Research Center. Eduardo J. Simoes, MD, MSc, is in University of Missouri School of Medicine, Department of Health Management and Informatics, Columbia, Missouri. Open in a separate window Disclosure The Missouri Cancer Registry and Research Center (MCR-ARC) is supported in part by a cooperative agreement between the Centers for Disease Control and Prevention (CDC) and the Missouri Department of Health and Senior Services (DHSS #U58/DP006299-01/02) and a Surveillance Contract between DHSS and the University of Missouri (MU).
Comparative Effectiveness of Adjuvant Chemotherapy in Early-Stage Breast Cancer: A Network Meta-analysis

Abstract Background There are several regimens recommended by the National Comprehensive Cancer Network (NCCN) for HER2-negative operable breast cancer. To our knowledge, no trials have yet been performed comparing these regimens head to head. We performed a network meta-analysis comparing the efficacy of NCCN-recommended chemotherapy regimens. Methods We searched Medline, Embase, Web of Science, the Cochrane Central Register of Controlled Trials, and World Health Organization (WHO) International Clinical Trials Registry Platform from inception to February 2020. We included randomized clinical trials comparing adjuvant regimens in predominantly node-positive operable breast cancer patients. We compared (1) DDACT, (2) TCx4 cycles, (3) TAC, and (4) ACWKT. Common comparators were (5) AC, (6) ACT, and (7) ACD. Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines were followed. The Cochrane risk of bias tool assessed quality of the studies. Odds ratios (ORs) were calculated as measures of treatment effects with AC as reference. We used Bayesian hierarchical random-effects models with noninformative priors for mixed multiple treatment comparisons. Effectiveness was estimated by disease-free and overall survival using ORs. Sensitivity analyses were performed. Safety outcomes included febrile neutropenia. Results We identified 7 randomized controlled trials with 16,332 patients. TC (odds ratio [95% confidence interval], 0.71 [0.36-1.40]), TAC (0.77 [0.37-1.57]), ACWKT (0.68 [0.34-1.38]), and DDACT (0.72 [0.35-1.42]) were similar for overall survival. TC (0.64 [0.36-1.14]), TAC (0.67 [0.39-1.15]), ACWKT (0.63 [0.37-1.07]), and DDACT (0.59 [0.35-1.01]) had similar disease-free survival benefit. With regard to toxicity, TAC (2.67 [0.30-21.04]) had the highest odds of febrile neutropenia. Conclusion The current generation of regimens are similar in efficacy. Given the lower toxicity of TCx4 comparatively, it is an acceptable alternative for lower-risk early-stage HER2-negative breast cancers.
New Science on the Open Science Grid

The Open Science Grid (OSG) includes work to enable new science, new scientists, and new modalities in support of computationally based research. There are frequently significant sociological and organizational changes required in transformation from the existing to the new. OSG leverages its deliverables to the large scale physics experiment member communities to benefit new communities at all scales through activities in education, engagement and the distributed facility. As a partner to the poster and tutorial at SciDAC 2008, this paper gives both a brief general description and some specific examples of new science enabled on the OSG. More information is available at the OSG web site: (http://www.opensciencegrid.org).
Reduction techniques for intramedullary nailing of tibial shaft fractures: a comparative study

Objectives To assess the impact of various reduction techniques on postoperative alignment following intramedullary nail (IMN) fixation of tibial shaft fractures. Design Retrospective comparative study. Setting Level I trauma center. Patients Four hundred twenty-eight adult patients who underwent IMN fixation of a tibial shaft fracture between 2008 and 2017. Intervention IMN fixation with use of one or more of the following reduction techniques: manual reduction, traveling traction, percutaneous clamps, provisional plating, or blocking screws. Main outcome measures Immediate postoperative coronal and sagittal plane alignment, measured as deviation from anatomic axis (DFAA); coronal and sagittal plane malalignment (defined as DFAA >5° in either plane). Results Four hundred twenty-eight patients met inclusion criteria. Manual reduction (MR) alone was used in 11% of fractures, and adjunctive reduction aids were used for the remaining 89%. After controlling for age, BMI, and fracture location, the use of traveling traction (TT) with or without percutaneous clamping (PC) resulted in significantly improved coronal plane alignment compared to MR alone (TT: 3.4°, TT+PC: 3.2°, MR: 4.5°, P = .007 and P = .01, respectively). Using TT+PC resulted in the lowest rate of coronal plane malalignment (13% vs 39% with MR alone, P = .01), and using any adjunctive reduction technique resulted in decreased malalignment rates compared to MR (24% vs 39%, P = .02). No difference was observed in sagittal plane alignment between reduction techniques. Intraclass correlation coefficient (ICC) results indicated excellent intraobserver reliability on both planes (both ICC>0.85), good inter-observer reliability in the coronal plane (ICC = 0.7), and poor inter-observer reliability in the sagittal plane (ICC = 0.05). Conclusions The use of adjunctive reduction techniques during IMN fixation of tibia fractures is associated with a lower incidence of coronal plane malalignment when compared to manual reduction alone. Level of evidence Therapeutic Level III.
Refining Telemedicine: A Plea From Healthcare Workers During a Pandemic

Telemedicine has been in existence for decades with little traction for global mainstream medicine. However, COVID-19 has exposed the importance of providing continued care for patients while minimizing the risk of exposure during pandemics. There has been robust growth in the use of telemedicine since the pandemic began, rendering safety in care provided by minimizing exposure to patients and healthcare workers. There has been tremendous growth and innovation in various digital applications that facilitate telehealth as the platforms continue to improve. Even in the absence of a pandemic, telemedicine allows for care of patients who may live in remote areas or have issues with transportation and comorbidities prohibiting ambulation. This study is based on a questionnaire for healthcare providers who have been exposed to telemedicine during COVID-19. A survey was shared in social media forums involving groups of physicians and nurse practitioners who were willing to take the survey. Telemedicine is one of the best approaches to handling situations like pandemics or disease surges. In these circumstances, a virtual visit is beneficial for social distancing if a laptop, smartphone, or tablet is available, along with internet or cellular coverage. This survey was conducted among healthcare workers of various specialties and it was found out that there was a considerable impetus for the continued benefit from telemedicine as an alternative to in-person visits for selected patients. Ongoing improvements in the quality of applications/tools, education, and cost are essential to maintain telemedicine. There is also a constant necessity for vast improvements in healthcare policies and reimbursements to allow for telemedicine to evolve.
Treatments of Differential Item Functioning: A Comparison of Four Methods:

Test fairness is critical to the validity of group comparisons involving gender, ethnicities, culture, or treatment conditions. Detection of differential item functioning (DIF) is one component of ...
Scalable Deep Convolutional Neural Networks for Sparse, Locally Dense Liquid Argon Time Projection Chamber Data

Deep convolutional neural networks (CNNs) show strong promise for analyzing scientific data in many domains including particle imaging detectors such as a liquid argon time projection chamber (LArTPC). Yet the high sparsity of LArTPC data challenges traditional CNNs which were designed for dense data such as photographs. A naive application of CNNs on LArTPC data results in inefficient computations and a poor scalability to large LArTPC detectors such as the Short Baseline Neutrino Program and Deep Underground Neutrino Experiment. Recently, submanifold sparse convolutional networks (SSCNs) have been proposed to address this class of challenges. We report their performance on a three-dimensional (3D) semantic segmentation task on simulated LArTPC samples. In comparison with standard CNNs, we observe that the computation memory and wall-time cost for inference are reduced by a factor of 364 and 33, respectively, without loss of accuracy. The same factors for 2D samples are found to be 93 and 3.1, respectively. Using SSCN and public 3D LArTPC samples, we present the first machine learning-based approach to the reconstruction of Michel electrons, a standard candle for energy calibration in LArTPC due to their very well-understood energy spectrum. We find a Michel electrons identification efficiency of 93.9% and a 96.7% purity. Reconstructed Michel electron clusters yield 95.4% in average pixel clustering efficiency and 95.5% in purity. The results are compelling in showing the strong promise of scalable data reconstruction technique using deep neural networks for large scale LArTPC detectors.
Measurement of xanthine oxidase in biological tissues.

Publisher Summary This chapter discusses the role of xanthine oxidase in biological tissues. Xanthine oxidase appears to exist in nature in two distinct functional forms, an oxidase (XO) and a dehydrogenase (XD). In addition, xanthine oxidase has a liberal substrate specificity that includes alcohols, aldehydes, and other purines, such as hypoxanthine. The conventional method for determining XO activity involves following the rate of uric acid (UA) formation from xanthine spectrophotometrically at 295 nm in the presence or absence of NAD + . Although this reaction is physiologically relevant and the substrate (xanthine) is highly specific for XO and XD, this procedure is limited by its lack of sensitivity. In addition, other compounds that absorb light at 295 nm may reduce the specificity of the assay. An improved procedure involves incubation of the enzyme with the same substrates, assaying for UA levels by high-performance liquid chromatography (HPLC). This allows for a longer incubation, and hence increasing sensitivity. HPLC analysis also permits the specific determination of UA formation, as NAD + , xanthine, ethylenediaminetetraacetic acid (EDTA), and perhaps other molecules relevant to the assay system all absorb light at 295 nm. The reaction pH of 7.8 is higher than physiologic intracellular pH to increase the sensitivity of the assay, as the pH optima of both XO and XD are 8.0 to 9.0.
Genotypic expression with different ages of dams: III. Weight traits of sheep.

Correlations between genetic expression in lambs when dams were young (1 yr), middle-aged (2 and 3 yr), or older (older than 3 yr) were estimated with three-trait analyses for weight traits. Weights at birth (BWT) and weaning (WWT) and ADG from birth to weaning were used. Numbers of observations were 7,731, 9,518, 9,512, and 9,201 for Columbia (COLU), Polypay (POLY), Rambouillet (RAMB), and Targhee (TARG) breeds of sheep, respectively. When averaged, relative estimates for WWT and ADG were similar across breeds. Estimates were variable across breeds. On average, direct heritability was greater when environment was young dams (.44 for BWT and .34 for WWT) than when environment was dams of middle age or older (.24 and .28 for BWT and .20 and .16 for WWT, respectively). Maternal heritability was greater when dams were middle-aged or older (.28 and .22 vs .18) for BWT but was greater when dams were younger (.10 vs .05 and .04) for WWT. The estimates of genetic correlations for direct effects across age of dam environments averaged .32 for birth weight and averaged .70 for weaning weight. Average estimates of maternal genetic correlations across age of dam classes were .36 or less for both BWT and WWT. Average estimates of correlations among maternal permanent environmental effects were .49 or less across age of dam classes. Total maternal effects accounted for .33 to .42 of phenotypic variance for BWT and for .09 to .26 of phenotypic variance for WWT. The average estimates of genetic correlations between expressions of the same genotypes with different ages of dams suggest that measurements of BWT of lambs with dams in young, middle, and older age classes should be considered to be separate traits for genetic evaluation and that for WWT measurements with young age of dam class and combined middle and older age of dam classes should be considered to be separate traits for genetic evaluation.
Evolving open learning environments using hypermedia technology

A number of features of web-based hypermedia are identified as providing a suitable medium for the design of open learning environments. The underlying object-oriented architecture of hypermedia systems accords with the need for representational diversity of pedagogic mechanisms and the ongoing re-construction that an evolutionary approach to the design of learning activity demands. A web-based prototype has been constructed to represent aspects of the National English Board curriculum in diabetes mellitus. The design and development process tries to take account of features of the environment likely to influence or be influenced by the intervention. Quantitative and qualitative methods have been employed to enable an evaluation of the hypermedia design and its environment of use.
A comparison of hydroxylamine and N-methylhydroxylamine as probes for the mechanism of action of the anthranilate synthetase of Escherichia coli.

Abstract In the presence of hydroxylamine, anthranilate synthetase catalyzes the formation of γ-glutamylhydroxamate. This activity requires enzyme, glutamine, and hydroxylamine and is stimulated by chorismate and inhibited by tryptophan. Measurement of the absorption at 500 nm of the red-violet γ-glutamylhydroxamate-Fe3+ chelate provides a convenient assay for the glutaminase activity of this enzyme. When N-methylhydroxylamine is present in the anthranilate synthetase reaction mixture, N-methylhydroxylamine derivatives of pyruvate are formed. One of these derivatives reacts with Fe3+ in acid to form a chromophore which absorbs at 500 nm. The production of these derivatives from pyruvate is nonenzymatic. Their appearance in the anthranilate synthetase reaction mixture is the result of the formation of pyruvate as a product of the enzymatic conversion of chorismate to anthranilate. Anthranilate synthetase is partially inhibited by N-methylhydroxylamine. This inhibition is largely attributable to contaminating Zn2+, a potent inactivator of this enzyme. These results cast doubt on earlier conclusions concerning the mechanism of action of anthranilate synthetase based on studies with N-methylhydroxylamine.
E-Commerce: The virtual battlefield

It seems reasonable that one would want to use intelligent agents with different ways of behaving to perform different tasks in e-commerce. This paper considers how intelligent agents might behave in e-commerce environments, if their behaviors were modeled after different human “personality characteristics.” In particular, an e-commerce agent based on Machiavelli’s principals is discussed and compared to one with anti-machiavellian behaviors.
SWiMNet: a scalable parallel simulation testbed for wireless and mobile networks

We present a framework, called SWiMNet, for parallel simulation of wireless and mobile PCS networks, which allows realistic and detailed modeling of mobility, call traffic, and PCS network deployment. SWiMNet is based upon event precomputation and a combination of optimistic and conservative synchronization mechanisms. Event precomputation is the result of model independence within the global PCS network. Low percentage of blocked calls typical for PCS networks is exploited in the channel allocation simulation of precomputed events by means of an optimistic approach.Various experiments were conducted to study the performance and scalability of SWiMNet using a realistic mobility model and executed on a cluster of workstations. Experimental results indicate that our parallel simulation model yields good speedup, and significantly reduces the execution time compared to a sequential implementation. Finally, an analytical study of our PCS simulation model is also presented and compared with the experimental results. Our model is found to be consistent with the analytical study.
Extending polynomial time computability to markets with demand correspondences

We present a polynomial time algorithm that computes an approximate equilibrium for any exchange economy with a demand correspondence satisfying gross substitutability. Such a result was previously known only for the case where the demand is a function, that is, at any price, there is only one demand vctor. The case of multi valued demands that is dealt with here arises in many settings, notably when the traders have linear utilities. We also show that exchange markets in the spending constraint model have demand correspodences satisfying gross substitutability and that they always have an equilibrium price vector with rational numbers. As a consequence, the framework considered here leads to the first exact polynomial time algorithm for this model.
Conflict of Interest Theory and Specific Systems: Postwar Italy and Weimar Germany

After examining conflict of interest theory and Axelrod's application of it to the postdiction of postwar Italian parliamentary coalitions, a replication of Axelrod's work is undertaken with Weimar Germany as the setting. Axelrod's theory is compared in terms of its predictability with other theories (the Von-Neumann-Morgenstern theory, Leiserson's bargaining theory, the basic and modified theories of William Riker, and De Swaan's policy distance theory). Axelrod's minimum-connected winning approach is shown to have a relatively higher predictive ability in postdicting Weimar coalition behavior. Some suggestions as to the modification of conflict-of-interest theory for application to “abnormal parliamentary periods” are offered in conclusion.
Phorbol esters potentiate evoked and spontaneous release by different presynaptic mechanisms.

Phorbol esters enhance release from a variety of cell types. The mechanism by which phorbol esters potentiate presynaptic release from central neurons is unclear, although effects of phorbol esters both on the readily releasable pool of vesicles and on presynaptic calcium channels have been shown. Using confocal microscopy and the fluorescent styryl dye FM 1-43, we have examined the effects of phorbol-12,13-dibutyrate (PDBu) on presynaptic vesicle turnover at individually identified synapses in dissociated cultures obtained from neonatal rat hippocampus. Using different dye staining and destaining protocols we were able to resolve two effects of PDBu. Potentiation of evoked release by PDBu was insensitive to calcium channel antagonists, suggesting that this effect results from an increased number of vesicles in the readily releasable pool. Since we observed no effect of PDBu on the size of the total recycling vesicle pool, we conclude that phorbol esters alter the equilibrium between reserve and readily releasable pools. An additional effect of PDBu on spontaneous release was observed. This effect was antagonized by nifedipine but not ω-conotoxin GVIA or ω-agatoxin IVA. We conclude that PDBu influences spontaneous and evoked release by two different mechanisms: through L-type calcium channels and through an increase in the proportion of recycling vesicles in the readily releasable pool. In addition to further clarifying the mechanism of action of phorbol esters, these results suggest that phorbol esters may be a useful tool with which to probe the function of the readily releasable pool of presynaptic vesicles at CNS synapses.
Continuous transversus abdominis plane (TAP) blocks for postoperative pain control after hernia surgery: a randomized, triple-masked, placebo-controlled study.

Background Single-injection transversus abdominis plane (TAP) block provides postoperative analgesia and decreases supplemental analgesic requirements. However, there is currently no evidence from randomized, controlled studies investigating the possible benefits of continuous TAP blocks. Therefore, the aim of this randomized, triple-masked, placebo-controlled study was to determine if benefits are afforded by adding a multiple-day, ambulatory, continuous ropivacaine TAP block to a single-injection block following hernia surgery. Methods Preoperatively, subjects undergoing unilateral inguinal (N = 19) or peri-umbilical (N = 1) hernia surgery received unilateral or bilateral TAP perineural catheter(s), respectively. All received a ropivacaine 0.5% (20 mL) bolus via the catheter(s). Subjects were randomized to either postoperative perineural ropivacaine 0.2% or normal saline using portable infusion pump(s). Subjects were discharged home where the catheter(s) were removed the evening of postoperative day (POD) 2. Subjects were contacted on POD 0–3. The primary endpoint was average pain with movement (scale: 0–10) queried on POD 1. Results Twenty subjects of a target 30 were enrolled due to the primary surgeon's unanticipated departure from the institution. Average pain queried on POD 1 for subjects receiving ropivacaine (N = 10) was a mean (standard deviation) of 3.0 (2.6) vs 2.8 (2.7) for subjects receiving saline (N = 10; 95% confidence interval difference in means −2.9 to 3.4; P = 0.86). There were no statistically significant differences detected between treatment groups in any secondary endpoint. Conclusions The results of this study do not support adding an ambulatory, continuous ropivacaine infusion to a single-injection ropivacaine TAP block for hernia surgery. However, the present investigation was underpowered, and further study is warranted.
Aflatoxins and Aflatoxicoses

Aflatoxins are a group of polyketide metabolites produced mainly by stains of the fungus Aspergillus flavus and the closely related species A. parasiticus. The most biologically active aflatoxin is B1; it is considered the most potent naturally occurring carcinogen known. Aflatoxins have been shown to produce cancer in all species tested; epidemiologic evidence suggests that they are involved in human liver cancer in some parts of the world. Therefore, many nations have set statutory limits on the concentration of aflatoxins in food and feed. Keywords: alfatoxins; polyketide metabolites; Aspergillus flavus; Aspergillus parasiticus; Food and Drug Administration; mycotoxin; carcinogen
Spotlight on neoadjuvant therapy for breast cancer.

Historically, the use of neoadjuvant therapy was considered only for patients with locally advanced or inflammatory breast cancer. Increasingly, systemic therapy is being given prior to surgery in patients with operable and early-stage breast cancer. Clinical trials have demonstrated that the use of neoadjuvant systemic therapy is equivalent to adjuvant therapy in terms of overall survival, and it increases the likelihood of successful breast-conserving therapy. As a result, patients who, at the time of presentation, are identified as meeting the criteria for receipt of adjuvant chemotherapy are being considered for delivery of the chemotherapy in the neoadjuvant setting. In addition to reduction in the size of the primary tumor, patients receiving neoadjuvant chemotherapy are less likely to have positive axillary nodes and may be candidates for nodesparing surgery. The pathologic assessment of the surgical specimens after neoadjuvant therapy provides information on the residual cancer burden (RCB) which correlates with disease-free survival outcomes. Neoadjuvant systemic therapy is no longer limited to chemotherapy but can include targeted agents and endocrine therapies specific for biologic subtypes. The neoadjuvant approach requires a multidisciplinary team, and communication across the disciplines is key to achieving optimal outcomes. In this special issue of Annals of Surgical Oncology is a series of articles focusing on the assessment and management of breast cancer patients treated with systemic therapy in the neoadjuvant setting. In the first article, Drs. Haddad and Goetz present an overview of the changing landscape of neoadjuvant therapy for breast cancer. 1 They review what has been learned from landmark trials in the field and how the approach has changed with the availability of targeted agents. When the treatment is targeted to the specific biologic subtype, the likelihood of response to therapy is significantly increased. They provide an overview of the RCB index and the
Biofeedback-assisted relaxation training for the aging chronic pain patient.

The older segments of the U.S. population are expanding rapidly and account for a disproportionate amount of health care, including treatment for pain-related musculoskeletal disorders. In a prospective study with objective measures and one-year follow-up, Middaugh et al. (1988) found that older patients (55–78 yr; N=17, 76% success) treated in a multidisciplinary chronic pain rehabilitation program enjoyed a success rate equal to that of younger patients (29–48 yr; N=20, 70% success). The current study presents additional data on these two groups of patients to compare their ability to learn the physiological self-regulation skills taught in the biofeedback/relaxation component of the multimodal program. This component included progressive muscle relaxation training, diaphragmatic breathing instruction, and EMG biofeedback. Repeated measures ANOVA showed significant increases in digital skin temperature (peripheral vasodilation) and decreases in respiration rate both within and across training sessions (p values=.04 to .0001) with no differences between age groups (p>.05). EMG measures for the upper trapezius ms in patients with cervical pain showed similar deficits in muscle control at evaluation and similar improvements with biofeedback training for the two age groups. These findings indicate that older pain patients responded well to the biofeedback/relaxation training component of the multimodal pain program.
Residential segregation in American cities: A contrary review

Clark (1986) has reviewed evidence on the causes of racial residential segregation in American cities and has concluded that economic factors, job locations, preferences, and information bear the predominant explanatory weight; private acts of housing discrimination carry little weight. This article argues that Clark's conclusions are erroneous because they are based on a selective and incorrect interpretation of the evidence available to him and because more recent studies provide strong evidence to the contrary.
Selecting and Utilizing Populus and Salix for Landfill Covers: Implications for Leachate Irrigation

The success of using Populus and Salix for phytoremediation has prompted further use of leachate as a combination of irrigation and fertilization for the trees. A common protocol for such efforts has been to utilize a limited number of readily-available genotypes with decades of deployment in other applications, such as fiber or windbreaks. However, it may be possible to increase phytoremediation success with proper genotypic screening and selection, followed by the field establishment of clones that exhibited favorable potential for cleanup of specific contaminants. There is an overwhelming need for testing and subsequent deployment of diverse Populus and Salix genotypes, given current availability of clonal material and the inherent genetic variation among and within these genera. Therefore, we detail phyto-recurrent selection, a method that consists of revising and combining crop and tree improvement protocols to meet the objective of utilizing superior Populus and Salix clones for remediation applications.
Cytochrome P450 CYP6X1 cDNAs and mRNA expression levels in three strains of the tarnished plant bug Lygus lineolaris (Heteroptera: Miridae) having different susceptibilities to pyrethroid insecticide

Three cDNAs, cloned from both pyrethroid-susceptible and -resistant strains of Lygus lineolaris, contained a 1548 nucleotide open reading frame encoding a 516 amino acid residue protein. Predicted cytochrome P450s from cDNAs were classified as the first three new members of subfamily CYP6X, CYP6X1v1 for a susceptible strain and CYP6X1v2 and CYP6X1v3 for two resistant strains. Putative cytochrome P450 CYP6X1s from L. lineolaris were highly similar (up to 42% amino acid sequence identity) to several insect CYP6s that are responsible for reduced sensitivity to pyrethroid insecticides. A total of twenty-six nucleotide substitutions were revealed between cDNAs of susceptible and resistant strains. Two nucleotide substitutions resulted in amino acid changes, Asp373 to Ala373 and Ser487 to Ala487, between susceptible and resistant strains. The resistant laboratory strain contained 2.1-fold higher cytochrome P450 mRNA per microgram total RNA than the susceptible laboratory strain. Topical treatment with 10 ng permethrin elevated cytochrome P450 mRNA levels by approximately 2-fold. The results of this study indicated that cytochrome P450 gene mutation, coupled with up-regulation, was present only in the pyrethroid resistant strains, and was possibly related to resistance development in the tarnished plant bug.
Chemical bonding and charge redistribution - Valence band and core level correlations for the Ni/Si, Pd/Si, and Pt/Si systems

Via a systematic study of the correlation between the core and valence level X-ray photoemission spectra, the nature of the chemical bonding and charge redistribution for bulk transition metal silicides has been examined. Particular emphasis is placed on Pt2Si and PtSi. It is observed that the strength of the metal (d)-silicon (p) interaction increases in the order Ni2Si, Pd2Si, Pt2Si. It is also observed that both the metal and silicon core lines shift to higher binding energy as the silicides are formed. The notion of charge redistribution for metallic bonds is invoked to explain these data.
223 CRYOPRESERVATION OF IMMATURE BOVINE CUMULUS–OOCYTE COMPLEXES BY SLOW RATE FREEZING AND VITRIFICATION

Cryopreservation of mature oocytes can result in damage to the metaphase spindle due to the temperature sensitivity of microfilaments and microtubules. Cryopreservation of immature oocytes may circumvent this problem because these structures have not formed yet and the genetic material is enclosed within a nuclear envelope. Because intact oocyte cumulus-oocyte complexes (COC) are essential for normal maturation, we chose to cryopreserve immature intact COC. The aim of this study was to determine if immature COC cryopreserved by slow rate freezing or vitrification would resume meiosis upon thawing. In 2 separate experiments, immature COC (n = 102 and 79) were collected from cross-bred cattle by transvaginal ultrasound-guided aspiration and divided into 2 groups. For both experiments, the first group (n = 64 and 40) was placed directly into maturation medium (TCM 199 supplemented with 10% fetal bovine serum, 0.2 mM sodium pyruvate, 2 mM glutamine, and 5 μg mL–1 of FSH) and cultured for 22 h under 5% CO2 in air atmosphere at 39°C. In experiment 1, COC (n = 38) in the second group were cryopreserved by a slow rate freezing protocol. The COC were equilibrated for 5 min in 1.5 M ethylene glycol (EG), and 5 COC were loaded into 0.25-mL straws and placed into the cooling chamber of a Freeze Control unit at –6°C. After 5 min, straws were seeded, then cooled at 0.5°C per min to –35°C before plunging into LN. After storage in LN for 5 days, straws were removed from LN, thawed by placing straws in a 35°C water bath, and COC put into maturation as described above. In experiment 2, COC (n = 39) in the second group were cryopreserved by vitrification using a 3-step procedure. The COC were equilibrated in solutions consisting of 10% glycerol then 10% glycerol and 20% EG in PBS for 5 min each. The COC were then placed in a solution of 24% glycerol and 26% EG, and 1 to 3 COC were placed onto a cryotop device in minimal medium and plunged into LN within 45 s. After storage in LN for 2 days, COC were thawed by placing the cryotop device directly into a warmed dilution solution consisting of 0.5 M galactose in PBS. After 5 min in the dilution solution, COC were put into maturation as described above. For all groups, after 22 h of maturation cumulus cells were stripped from the oocytes by vortexing and oocytes were placed on slides for fixation in methanol acetic acid and stained with 1% orcein to determine the nuclear stage. In experiment 1, oocytes cryopreserved by slow rate freezing matured to MII at the same rate as control oocytes (45 v. 55%, P = 0.44). In experiment 2, oocytes cryopreserved by vitrification matured to MII at a lower rate than controls (49 v. 79%, P = 0.01). These results show that cryopreservation of immature intact COC is a viable alternative to cryopreservation of mature oocytes. Further studies are needed to optimize either slow rate freezing or vitrification of intact COC and determine the developmental competence of cryopreserved oocytes following fertilization.
Toward a theory of learned hopefulness: A structural model analysis of participation and empowerment.

Two competing structural models were tested in an effort to develop a theory of learned hopefulness. Learned hopefulness suggests that empowering experiences-ones that provide opportunities to learn skills and develop a sense of control-can help individuals limit the debilitating effects of problems in living. Voluntary organizations are identified as natural settings that enable individuals to develop a sense of psychological empowerment. Empowerment was measured by cognitive, personality, and motivational measures of perceived control. Structural equation modeling was used to compare models for a sample of students and a sample of nonstudent community residents. The model which supports the theory of learned hopefulness included a direct effect of participation in voluntary organizations on psychological empowerment. An alternative model omitted the path between participation and empowerment. The learned hopefulness model reproduced the observed data with less error than the alternative model. The results provide support for a theory of learned hopefulness and suggest that future research to fully develop the theory is warranted. CC 19w
Ruptured splenic artery aneurysm in pregnancy. Twelfth reported case with maternal and fetal survival.

Ruptured splenic artery aneurysm during pregnancy is a rare event with catastrophic consequences. This presentation is the twelfth case during pregnancy reporting survival of both mother and fetus. The literature reports a 25% mortality rate for ruptured splenic artery aneurysm. The mortality rate among pregnant women is disproportionately high at 75% with a fetal mortality rate of 95%. Gestational alterations that increase with parity are significant in the pathophysiologic characteristics of this condition. A unique double-rupture phenomenon may provide temporary tamponade with resolution of symptoms. A diagnosis of ruptured splenic artery aneurysm should be considered in any pregnant patient who complains of the sudden onset of severe left upper-abdominal pain regardless of whether pain or shock is prominent at the time of evaluation. Early consideration of a diagnosis of ruptured splenic artery aneurysm significantly increases the likelihood that the mother and fetus will survive. (AM J OBsTET GVNECOL 1993;168:1810-3.)
PHYTOPLANKTON DYNAMICS AND THE ROLE OF GRAZERS IN CASTLE LAKE, CALIFORNIA'

During summer 1987, a series of experiments was performed in conjunction with monitoring of in situ plankton dynamics in nutrient-deficient Castle Lake, California. These factorial manipulations of nutrients and zooplankton were designed to separate the direct (grazing mortality) and indirect (stimulation of algal growth by nutrient recycling) effects of grazers on both species-specific phytoplankton dynamics, as well as aggregate properties such as total biomass, productivity, and biomass turnover. Grazing loss rates differed significantly among algal species with the mean grazing loss rate suffered by an algal species a negative function of cell or colony size. Stimulation of division rates in the presence of zooplankton (compared to an unenriched treatment lacking zooplankton) was commonly observed. Nutrient and grazer treatments also had significant impacts on algal biomass (indicated by chlorophyll concentration), productivity (PPR), and PPR/chloro- phyll, and significant nutrient-grazer interactions were frequently observed. Species-specific algal responses to grazers were aggregated across the phytoplankton by weighting species- specific parameters by the contribution of each species to total community biomass in order to provide community-wide estimates of the importance of direct and indirect effects on algal dynamics. Finally, linkages between population-level responses and aggregate properties were demonstrated by examining relationships between total phytoplankton biovolume concentration and chlorophyll concentration in various treatments, by com- paring community-wide grazing rates estimated from aggregated species-specific grazing rates and from changes in chlorophyll growth rates, and by relating the aggregated degree of species-specific growth stimulation to stimulation of biomass turnover. These results indicate that phytoplankton responses to grazers in Castle Lake reflect a mix of direct and indirect effects that varies considerably both between species and through time during the stratified season.
Effectiveness of oxygen therapy in hypoxic polycythemic smokers.

Eleven hypoxic (arterial oxygen pressure [PaO 2 ] ≤ 61 mm Hg), polycythemic (hematocrit reading ≥ 54 percent) patients were studied to determine the effect of the carboxyhemoglobin level on their response to therapy with supplemental oxygen. Five nonsmokers with a mean carboxyhemoglobin level of 2.8 percent showed an exexcellent response to therapy with supplemental oxygen, with a decrease in hematocrit reading from 57 percent to 48 percent (P 2 increased from 53 mm Hg to 69 mm Hg (P 2 ) increased from 86 percent to 94 percent (P 2 increased from 53 mm Hg to 69 mm Hg (P 2 increased from 82 percent to 88 percent (P 2 , the smokers had higher hematocrit readings before and during therapy with oxygen (P