cssi/SciSciGPT-SciSciNet huggingface dataset:
Does sentinel lymph node status have prognostic significance in patients with acral lentiginous melanoma

BACKGROUND The prognostic benefit of sentinel lymph node biopsy (SLNB) and factors predictive of survival specifically in patients with acral lentiginous melanoma (ALM) are unknown. METHODS The SEER database was queried for ALM cases that underwent SLNB from 1998 to 2013. Clinicopathological factors were correlated with SLN status, overall survival (OS), and melanoma-specific survival (MSS). RESULTS Median age for the 753 ALM study patients was 65 years, and 48.2% were male. Median thickness was 2 mm with 38.1% of cases having ulceration. SLN metastases were detected in 194 of 753 cases (25.7%). Multivariable analysis showed that thickness, Clark level IV-V, and ulceration significantly predicted for SLN metastasis (P < 0.05). For patients with positive SLN, 5-year OS and MSS were significantly worse at 48.1% and 58.9%, respectively, compared with 78.7% and 88.5%, respectively, for patients with negative SLN (P < 0.0001). On multivariable analyses, older age, male gender, increasing thickness, ulceration, and a positive SLN significantly predicted for worse OS and MSS (all P < 0.05). CONCLUSION This study confirms the important role of SLNB in ALM. SLN metastases are seen in 25.7% of ALM cases, providing significant prognostic information. In addition, thickness, ulceration status, and SLNB status significantly predict survival in patients with ALM.
Enacting voices: An analysis on the complexity, accuracy, and fluency of heteroglossic speech

Abstract The present study supports the idea of heteroglossia and its contributions to language learning in second language acquisition (SLA) theory and bilingualism. Bakhtin’s (1934/1981) theory of heteroglossia differs from variety and register in that when acquiring a language, one internalizes the voices of others. Viewing interlanguage through a heteroglossic lens, it is possible that these voices in heteroglossia may have an effect on second language (L2) users’ language production. By blending sociolinguistic and sociocultural frameworks, this study analyzed the complexity, accuracy, and fluency of two French-English bilinguals’ narratives. Findings demonstrate a clear shift in all three measures of the CAF framework when participants enacted the voice of a perceived interlocutor or perceived self, versus when they recounted a narrative. These findings support the notion that an individual may have variable linguistic systems, and raise other important theoretical and practical implications for SLA research and L2 instruction.
Sub-Prime Mortgages And The Big Bang

Delinquencies and failures of sub-prime mortgages provide evidence that the housing bubble has burst. This study traces the creation of the housing bubble and examines the impact of the sub-prime debacle on world financial markets.
Serum interleukin 6 could be a valuable initial diagnostic tool in prosthetic knee joint infections

Accurate preoperative diagnosis of prosthetic joint infection (PJI) in the absence of obvious clinical signs or laboratory findings is challenging. Interleukin 6 (IL-6) has been proposed as an infection marker but supportive data are limited. We studied the diagnostic utility of serum IL-6 in infected total knee arthroplasty (TKA). A prospective cohort study was done in 52 patients (59 knees) with a painful TKA. The abnormal limits for serum IL-6, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), synovial fluid white cell counts (WBC) and synovial fluid neutrophils (PMN) were determined from receiver operating characteristic curves. An infection was defined as the presence of sinus tract or positive culture > two separate tissue or fluid samples. We utilized Mann–Whitney test, Spearman’s correlation and Fischer’s exact test to determine the sensitivity, specificity, positive predictive value, negative predictive value (NPV) and accuracy of serum IL-6. The optimal threshold concentration of serum IL-6 was 9.14 pg/ml. Independently, this yielded a sensitivity, specificity and NPV of 81%, 63% and 85%, respectively, and when combined with synovial fluid WBC, values were 100%, 90%, 100%, respectively. The sensitivity and specificity of ESR (70%, 63.6%), CRP (66.7%, 66.7%), synovial WBC (66.7%, 81%) and synovial PMN (82.4%, 73.7%) were also calculated. Serum IL-6 levels strongly correlate with all markers in PJI. Serum IL-6 improves the diagnosis of PJI over existing methods, especially when combined with synovial fluid WBC. Its optimal usage is as an excellent screening test to rule out infected total knee arthroplasty. Diagnostic Level II.
Support Vector Based Autoregressive Mixed Models of Longitudinal Brain Changes and Corresponding Genetics in Alzheimer’s Disease

Longitudinal data used as repeat measures may capture the proportion of total variance due to genetic factors with greater sensitivity. However, for brain imaging in studies of older adults, there is a steady decline of brain tissue. It is important to establish such estimation methods using longitudinal data, while properly modeling within-subject variation and rate of tissue atrophy. However, to date, neuroimaging studies have been limited to using only two timepoints, and have not considered diagnostic-specific trends in clinically heterogeneous samples. Modeling temporal patterns of brain structure specific to neurodegenerative disease, while simultaneously assessing the contribution of genetic and environmental risk factors, is essential to understanding and predicting disease progression. We use data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) to model the genetic effects on brain cortical measurements from three repeated measures across two years. We refine our model for specific diagnostic groups, including cognitively normal elderly individuals, individuals with mild cognitive impairment and AD, and then distinguish between those who remain stable or convert to AD. We propose a support vector based, longitudinal autoregressive linear mixed model (ARLMM) for long-term repeated measurements, offering greater sensitivity than cross-sectional analyses in baseline scans alone.
Various Human Hematopoietic Growth Factors (Interleukin-3, GM-CSF, G-CSF) Stimulate Clonal Growth of Nonhematopoietic Tumor Cells

We have studied the effect of recombinant human hematopoietic growth factors (interleukin-3 [rhIL-3], granulocyte-macrophage colony-stimulating factor [rhGM-CSF], and granulocyte CSF [rhG-CSF]) on the clonal growth of human colon adenocarcinoma cell lines HTB-38, CCL 187, and WiDr (CCL 218). The factors stimulated clonal growth of HTB-38 and CCL 187 in a capillary modification of the human tumor clonogenic assay in agar up to twofold. There were dose-response correlations over a range of 1 to 10,000 U/mL for rhIL-3, rhGM-CSF, and rhG-CSF. Incubation with neutralizing monoclonal antibodies abolished the stimulation of clonal growth by rhGM-CSF. The WiDr cell line was nonresponsive to rhIL-3 and rhGM-CSF. These results represent the first evidence that a variety of hematopoietic growth factors can stimulate the growth of clonogenic cells of some nonhematopoietic malignant cell lines in vitro.
Energy Minimization of Two Dimensional Incommensurate Heterostructures

We derive and analyze a novel approach for modeling and computing the mechanical relaxation of incommensurate two dimensional heterostructures. Our approach parametrizes the relaxation pattern by the compact local configuration space rather than real space, thus bypassing the need for the standard supercell approximation and giving a true aperiodic atomistic configuration. Our model extends the computationally accessible regime of weakly coupled bilayers with similar orientations or lattice spacing, for example materials with a small relative twist where the widely studied large-scale moire patterns arise (Kim et al. in Proc Natl Acad Sci 114:3364–3369, 2017; Yoo et al. in Atomic and electronic reconstruction at van der Waals interface in twisted bilayer graphene, Nat Mater 18:448–453, 2019). Our model also makes possible the simulation of multi-layers for which no inter-layer empirical atomistic potential exists, such as those composed of $$\hbox {MoS}_2$$ layers, and more generally makes possible the simulation of the relaxation of multi-layer heterostructures for which a planar moire pattern does not exist.
Analysis of Effects of Distribution System Resources on Transmission System Voltages using Joint Transmission and Distribution Power Flow

With higher penetration of distributed photovoltaic (PV) resources and wider adoption of electric vehicles (EVs), it is reasonable to expect events at the distribution level to more actively influence the state of the network. However, traditional power flow formulations mostly consider either the transmission system or the distribution system. Recent work has been done in the development of a joint transmission and distribution (T&D) formulation to properly account for interactions between the two systems. This paper presents the analysis of effects of distribution system resources on transmission system voltages. The analysis relies on a recently developed power flow tool that combines distribution and transmission circuits. Results of multi-period power flow simulations are shown demonstrating how the location of PV and EV fast charging facilities in distribution circuits affects transmission bus voltages. Furthermore, the results are analyzed, and justifications are offered to explain the observed phenomena.
Neoadjuvant radiation therapy versus resection alone in the management of non-metastatic retroperitoneal soft tissue sarcoma: A review of the literature

Abstract Surgery is the mainstay of therapy for primary, non-metastatic, retroperitoneal sarcomas. However, even after curative intent surgery, local recurrence rates are high and can lead to significant morbidity and mortality. The utility of neoadjuvant radiation therapy has been debated, although most published data has been from retrospective studies. The recent publication of the STRASS trial represents the first completed, multi-center, prospective, randomized controlled trial of neoadjuvant radiation plus surgery versus surgery alone. In this article, we review the importance of local control for retroperitoneal sarcomas, summarize the findings of the published data, highlighting the STRASS trial, and review the potential toxicities of retroperitoneal radiation therapy. Although the STRASS trial is largely considered a negative trial, it highlights key themes in understanding the biology of various histologic subtypes and potential areas for further study.
Understanding On-Campus Interactions With a Semiautomated, Barcode-Based Platform to Augment COVID-19 Contact Tracing: App Development and Usage.

Background: The COVID-19 pandemic has forced drastic changes to daily life, from the implementation of stay-at-home orders to mandating facial coverings and limiting in-person gatherings. While the relaxation of these control measures has varied geographically, it is widely agreed that contact tracing efforts will play a major role in the successful reopening of businesses and schools. As the volume of positive cases has increased in the United States, it has become clear that there is room for digital health interventions to assist in contact tracing. Objective: The goal of this study was to evaluate the use of a mobile-friendly app designed to supplement manual COVID-19 contact tracing efforts on a university campus. Here, we present the results of a development and validation study centered around the use of the MyCOVIDKey app on the Vanderbilt University campus during the summer of 2020. Methods: We performed a 6-week pilot study in the Stevenson Center Science and Engineering Complex on Vanderbilt University’s campus in Nashville, TN. Graduate students, postdoctoral fellows, faculty, and staff >18 years who worked in Stevenson Center and had access to a mobile phone were eligible to register for a MyCOVIDKey account. All users were encouraged to complete regular self-assessments of COVID-19 risk and to key in to sites by scanning a location-specific barcode. Results: Between June 17, 2020, and July 29, 2020, 45 unique participants created MyCOVIDKey accounts. These users performed 227 self-assessments and 1410 key-ins. Self-assessments were performed by 89% (n=40) of users, 71% (n=32) of users keyed in, and 48 unique locations (of 71 possible locations) were visited. Overall, 89% (202/227) of assessments were determined to be low risk (ie, asymptomatic with no known exposures), and these assessments yielded a CLEAR status. The remaining self-assessments received a status of NOT CLEAR, indicating either risk of exposure or symptoms suggestive of COVID-19 (7.5% [n=17] and 3.5% [n=8] of self-assessments indicated moderate and high risk, respectively). These 25 instances came from 8 unique users, and in 19 of these instances, the at-risk user keyed in to a location on campus. Conclusions: Digital contact tracing tools may be useful in assisting organizations to identify persons at risk of COVID-19 through contact tracing, or in locating places that may need to be cleaned or disinfected after being visited by an index case. Incentives to continue the use of such tools can improve uptake, and their continued usage increases utility to both organizational and public health efforts. Parameters of digital tools, including MyCOVIDKey, should ideally be optimized to supplement existing contact tracing efforts. These tools represent a critical addition to manual contact tracing efforts during reopening and sustained regular activity.
Using Tax Deductions to Promote Lifelong Learning: Real and Shifting Responses

Policymakers are concerned about potential underinvestment in lifelong learning. In this paper we study to what extent a tax deduction helps to stimulate post-initial training. Specifically, we employ a regression kink and regression discontinuity design as jumps in tax bracket rates generate exogenous variation in the effective costs of lifelong learning. Using high quality data on tax returns of the universe of Dutch taxpayers, we find that the tax deduction has heterogeneous effects on lifelong learning. Low-income singles show no response. For high-income singles we find an effect of 10% on the probability to use the tax deduction. Furthermore, ignoring shifting of expenses between partners leads to spurious large estimates for primary earners and spurious negative estimates for secondary earners.
How Online Learners Build Cognitive Presence: Implications from a Machine Learning Approach

Within the last year, the number of students who participate in online learning platforms has exploded. The transition to online platforms has moved discussion out of the classroom and onto digital spaces. To support this transition we aim to create a model which can help teachers and teaching assistants understand how the discourse of learners in discussion forums evolve through multiple phases of cognitive presence over time.To this end, we use cutting-edge natural language processing techniques and apply machine-learning algorithms to build a model that can predict the cognitive presence phase of posts based on the community of inquiry framework.
Ocean dynamic equations with the real gravity

Two different treatments in ocean dynamics are found between the gravity and pressure gradient force. Vertical component is 5–6 orders of magnitude larger than horizontal components for the pressure gradient force in large-scale motion, and for the gravity in any scale motion. The horizontal pressure gradient force is considered as a dominant force in oceanic motion from planetary to small scales. However, the horizontal gravity is omitted in oceanography completely. A non-dimensional C number (ratio between the horizontal gravity and the Coriolis force) is used to identify the importance of horizontal gravity in the ocean dynamics. Unexpectedly large C number with the global mean around 24 is obtained using the community datasets of the marine geoid height and ocean surface currents. New large-scale ocean dynamic equations with the real gravity are presented such as hydrostatic balance, geostrophic equilibrium, thermal wind, equipotential coordinate system, and vorticity equation.
A 3D Mirroring and Colormap Asymmetry Study of Class II Subdivision Patients.

INTRODUCTION Patients with Class II subdivision malocclusion present skeletal and dental asymmetries. The purpose of this study is to assess those asymmetries by 3D mirroring and colormap quantification. METHODS This study analyzed 50 initial CBCTs divided in two groups: Class I (control group) and Class II subdivision (study group) malocclusion patients. CBCTs were oriented and full skull was segmented generating a 3D model. The right side of the 3D models was mirrored, using a midsagittal plane as reference, resulting in a perfectly symmetric skull based on two right sides. Original and mirrored models were superimposed on the unchanged right half, and differences were quantified using a colormap. Eight regions of interest were assessed: gonion, mandibular front, maxillary front, zygomatic process, maxillary and mandibular canine and molar areas. RESULTS Statistically significant differences using the Mann Whitney test were found in six of the eight evaluated areas when comparing the control to the study group. The maxillary areas did not show any difference between the groups. CONCLUSIONS Patients with Class II subdivision malocclusion show true skeletal and dental asymmetries when comparing right and left sides. The maxilla showed no significant skeletal asymmetry, but the maxillary teeth were positioned more mesially on the Class II side. The maxillary canine on the Class II side was also more bucally positioned. The mandible showed significant asymmetries with both skeletal and dental areas in the Class II side more distally and bucally positioned.
Hewett Cottrell Watson

Introduction - Watson's significance Psychobiography or not? Chapter organization. Part I Finding a Place in the World: "As the twig is bent, so grows the tree", 1804-28 Edinburgh and career possibilities, 1828-32 - The city and phrenology The university and plant geography. Part II The Life of a Gentleman Scientist: Relationships and social perspectives, 1833-59 Private life Family life Phrenological struggles, 1833-40 outlook and social responsibilities, 1835-60 Science and religion Political and social views Continuing plant geography studies, 1833-48 In Britain In the Azores Islands Relationship with William Hooker, 1833-50 seeking employment, 1842-48 professional relationships with Forbes, Babington and Balfour, 1833-59 Conflict with Edward Forbes Botanical colleagues - Watson versus Babington and Balfour Botanical societies - Edinburgh versus London History not quite repeated - Watson, the botanical society Of london and the phytologist, 1840-58 the origin and transmutation of species, 1833-47 Watson's orientation and studies Darwin's orientation and studies Darwinian parallels and contrasts, 1809-58 Early life and personality Early thoughts on brain and emotions Early studies on biogeography Private and family life outlook and social responsibilities In the Azores Involvements with science and scientists Stonecutter for Darwin's edifice, 1847-1859 - Watson's own scientific conclusions A colleague for Darwin. Part III Later Life, Work, and Influences: Later life, work and influences, 1860-81 Doubts on the Darwinian revolution A synthesis on the botany of the Azores Relationship with Joseph Hooker A protege for Watson Watson's other relationships and influences Darwinian parallels and contrasts, 1860-82: Later work Later life Influences. Conclusions: Personality - Watson's Darwin's Difficult personalities within scientific communities Scientific achievements.
Dominance Behaviors and Hierarchies in Male and Female Groups

The previous two chapters have provided a qualitative account of early adolescent interactions, more characteristic of anthropologists and ethologists than of psychologists. In the present chapter I count numbers, comparing the behaviors, group structures, and status characteristcs of the male and female adolescents in cabin groups One through Eight. A follow-up study, a questionnaire sent to the early adolescent boys several years after their camp session, and an all-camp study are described in the next section. An extended discussion focusing on a comparison of the sexes follows the presentation of the data.
Where and When is Modernism: Editing on a Global Scale

The paper explores some longstanding definitional problems in literary modernism with specific reference to studying modernism on a global scale: What counts as modernism once we start to look for signs of it across the globe? The author examines the question in the context of his recent editorial project, Global Modernisms, which draws together multiple international and disciplinary perspectives in order to create a discursive space in which a wide range of foreign language productions can be brought into productive dialogue. Raising the question of whether a distinction between “modern” and “modernist” can be sustained, he suggests the need for continuing efforts of recursive definition as the field expands in order to maintain a viable object of study.
Identification of the primary mechanism of complement evasion by the periodontal pathogen, Treponema denticola

Summary Treponema denticola, a periodontal pathogen, binds the complement regulatory protein Factor H (FH). Factor H binding protein B (FhbB) is the sole FH binding protein produced by T. denticola. The interaction of FhbB with FH is unique in that FH is bound to the cell and then cleaved by the T. denticola protease, dentilisin. A ∼ 50-kDa product generated by dentilisin cleavage is retained at the cell surface. Until this study, a direct role for the FhbB–FH interaction in complement evasion and serum sensitivity had not been demonstrated. Here we assess the serum resistance of T. denticola strain 35405 (Td35405wt) and isogenic mutants deficient in dentilisin (Td35405-CCE) and FhbB production (Td35405ΔfhbB), respectively. Both dentilisin and FhbB have been postulated to be key virulence factors that mediate complement evasion. Consistent with conditions in the subgingival crevice, an environment with a significant concentration of complement, Td35405wt was resistant to serum concentrations as high as 25%. Deletion of fhbB (Td35405ΔfhbB), which resulted in the complete loss of FH binding ability, but not inactivation of dentilisin activity (Td35405-CCE), rendered T. denticola highly sensitive to 25% human serum with 80% of the cells being disrupted after 4 h of incubation. Heat treatment of the serum to inactivate complement confirmed that killing was mediated by complement. These results indicate that the FH–FhbB interaction is required for serum resistance whereas dentilisin is not. This report provides new insight into the novel complement evasion mechanisms of T. denticola.
Detection of human cytomegalovirus in plasma of AIDS patients during acute visceral disease by DNA amplification.

By using the polymerase chain reaction (PCR) amplification procedure, 19 (83%) of 23 plasma specimens obtained from individuals with AIDS and human cytomegalovirus (HCMV) visceral disease were found to be positive for plasma viremia as detected by PCR (PV-PCR), whereas 78% of cultures of peripheral blood leukocytes from the same samples were found to be positive. All 11 specimens prospectively obtained from individuals with acute HCMV disease were positive by PV-PCR. Plasma specimens from patients who received ganciclovir therapy rapidly became both culture and PV-PCR negative, and there was an excellent correlation between the two procedures. DNA detected by PV-PCR was unaffected by filtering plasma through a 0.2-microns-pore-size filter, although a conserved cellular gene, HLA-DQ alpha, was undetectable by PCR following filtration. HCMV DNA in plasma could be quantitated by PV-PCR by using endpoint serial dilutions, with detectable virus being present in 10(1) to 10(-2) microliters of plasma. A low titer of infectious virus could be detected in 2 of 11 plasma samples. The detection of HCMV DNA in plasma by PV-PCR promises to be a useful procedure for monitoring patients with AIDS suspected of having impending, acute, or recurrent HCMV visceral disease and suggests an additional route by which virus may disseminate in the immunocompromised host. Images
Dissent in Organizations, by Kassing, J

“If everyone is thinking alike, then someone isn't thinking.” —General George S. Patton, Jr. Without people who will voice their opinions and push for reform, organizations would have a hard time c...
Analyzing web service choreography specifications using colored Petri nets

Enacting cross-organizational business processes requires critical support for long-running and complex interactions involving multiple participants. The Web Services Choreography Description Language (WS-CDL) aims at facilitating just that, by providing means to describe correlated message exchanges among services geared towards achieving a business goal. While WSCDL specifications are machine-readable documents, they do not necessarily allow developers to determine--by direct inspection--whetheror not the patterns of message exchanges they stipulate do indeed describethe intended service behavior. In this research paper, we show how Colored Petri Nets (CPN) can be used to analyze WS-CDL documents in order to identify faults in the specification. We have developed a research prototype that assists in the creation of a CPN model from a given WS-CDL document. The CPN model generated is then analyzed using the formal verification environment and simulation capability provided by CPN-Tools. We provide a discussion on the analysis of an example WS-CDL document using this approach, as well as on the advantages and limitations of using CPN for analyzing WS-CDL specifications.
CB2: a cannabinoid receptor with an identity crisis

CB2 was first considered to be the ‘peripheral cannabinoid receptor’. This title was bestowed based on its abundant expression in the immune system and presumed absence from the central nervous system. However, multiple recent reports question the absence of CB2 from the central nervous system. For example, it is now well accepted that CB2 is expressed in brain microglia during neuroinflammation. However, the extent of CB2 expression in neurons has remained controversial. There have been studies claiming either extreme-its complete absence to its widespread expression-as well as everything in between. This review will discuss the reported tissue distribution of CB2 with a focus on CB2 in neurons, particularly those in the central nervous system as well as the implications of that presence. As CB2 is an attractive therapeutic target for pain management and immune system modulation without overt psychoactivity, defining the extent of its presence in neurons will have a significant impact on drug discovery. Our recommendation is to encourage cautious interpretation of data that have been presented for and against CB2's presence in neurons and to encourage continued rigorous study. This article is part of a themed issue on Cannabinoids. To view the editorial for this themed issue visit http://dx.doi.org/10.1111/j.1476-5381.2010.00831.x
Polyethylene glycol improves function and reduces oxidative stress in synaptosomal preparations following spinal cord injury.

Spinal cord injury (SCI) results in rapid and significant oxidative stress. We have previously demonstrated that administration of polyethylene glycol (PEG) inhibits oxidative stress using an in vitro model of SCI. In this study we tested the effects of PEG in vivo, to elucidate the mechanism of PEG-mediated neuroprotection. We show that a compression injury at T10–11 induced diffusive oxidative stress in crude synaptosomal preparations, correlated with synaptosomal dysfunction and increased intrasynaptosomal calcium. Administration of PEG immediately post-injury produced a marked decrease in synaptosomal oxidative stress and calcium, associated with an increase in synaptosomal function. Confocal microscopy using fluorescein conjugated PEG revealed that PEG entered the cells of the injured spinal cord, placing the polymer in a position to directly interact with cellular organelles. PEG attenuates calcium-induced functional compromise of normal spinal cord synaptosomes and mitochondria in vitro. These resu...
Intramolecular general base catalyzed transesterification: The cyclization of ethyl 2-hydroxymethylbenzoate and ethyl 2-hydroxymethyl 4-nitrobenzoate to phthalide and 5-nitrophthalide☆

The rates of cyclization of ethyl 2-hydroxymethylbenzoate to phthalide have been measured in H2O at 30°C with μ = 0.5. There is pronounced general base catalysis in the reaction with β = 0.87. The second-order rate constant for imidazole general base catalysis is decreased in D2O as compared with H2O by a factor of 3.46. The pH-rate constant profile obtained by extrapolation to zero buffer concentration shows hydronium ion and apparent hydroxide ion catalysis. The value of the second-order rate constant kOH is 105 greater than kOH for hydrolysis of ethyl benzoate. Ethyl 2-hydroxymethyl 4-nitrobenzoate cyclizes to 5-nitrophthalide in a similar manner. The Bronsted coefficient β for general base catalysis is 0.97, within error of unity. Thus, it is probable that general base catalysis involves rate-determining proton transfer.
Propensity score matching with time-dependent covariates.

Summary In observational studies with a time-dependent treatment and time-dependent covariates, it is desirable to balance the distribution of the covariates at every time point. A time-dependent propensity score based on the Cox proportional hazards model is proposed and used in risk set matching. Matching on this propensity score is shown to achieve a balanced distribution of the covariates in both treated and control groups. Optimal matching with various designs is conducted and compared in a study of a surgical treatment, cystoscopy and hydrodistention, given in response to a chronic bladder disease, interstitial cystitis. Simulation studies also suggest that the statistical analysis after matching outperforms the analysis without matching in terms of both point and interval estimations.
Study on the cellular factor of delayed hypersensitivity.

Abstract This study has demonstrated that the passive transfer of tuberculin-type hypersensitivity from hypersensitive to normal guinea pigs is due to a factor (DH factor) which can be adsorbed to tubercle bacilli or to red blood cells sensitized with bacillary products. This factor was found to be present in extracts of cells but not in serum of hypersensitive guinea pigs. The absence of DH factor in serum as well as its affinity to normal splenic cells suggests that the factor of delayed hypersensitivity is a separate entity from classical antibody. Injections of hypersensitive cell extract into heterologous species of animals induced the formation of antibodies. When such antisera were combined with the hypersensitive cell extract before the injection into the normal animal, the transfer of delayed hypersensitivity was neutralized.
Improved nonorthogonal tight-binding Hamiltonian for molecular-dynamics simulations of silicon clusters

We present an improvement over the nonorthogonal tight-binding molecular-dynamics scheme recently proposed by Menon and Subbaswamy [Phys. Rev. B 47, 12 754 (1993)]. The proper treatment of the nonorthogonality and its effect on the Hamiltonian matrix elements has been found to obviate the need for a bond-counting term, leaving only two adjustable parameters in the formalism. With the improved parametrization we obtain values of the energies and bonding distances which are in better agreement with the available ab initio results for clusters of size up to N=10. Additionally, we have identified a lowest energy structure for the ${\mathrm{Si}}_{9}$ cluster, which to our knowledge has not been considered to date. We show that this structure (a distorted tricapped trigonal prism with ${\mathit{C}}_{2\mathit{v}}$ symmetry) is also a minimum at the Hartree-Fock level and in approximate density-functional theory, and should therefore be seriously considered as a candidate for the ground-state structure of the ${\mathrm{Si}}_{9}$ cluster.
PRO and subject of NP

In the preceding sections, we have examined a number of roles that PRO in the specifier of an NP might play in relating the interior of the NP to its exterior, with respect to the principles of the binding theory, bound pronouns, and control. In each instance, positing PRO in NP helped with only an arbitrary subset of the cases. The implicit arguments view outlined here encompasses the full range of cases.
Comparisons of the Variability of Three Markers of the Human Circadian Pacemaker

A circadian pacemaker within the central nervous system regulates the approximately 24-h physiologic rhythms in sleep cycles, hormone secretion, and other physiologic functions. Because the pacemaker cannot be examined directly in humans, markers of pacemaker function must be used to study the pacemaker and its response to environmental stimuli. Core body temperature (CBT), plasma cortisol, and plasma melatonin are three marker variables frequently used to estimate the phase of the human pacemaker. Measurements of circadian phase using markers can contain variability due to the circadian pacemaker itself, the intrinsic variability of the marker relative to the pacemaker, the method of analysis of the marker, and the marker assay. For this report, we compared the mathematical variability of a number of methods of identifying circadian phase from CBT, plasma cortisol, and plasma melatonin data collected in a protocol in which pacemaker variability was minimized using low light levels and regular timing of both the light pattern and the rest/activity schedule. We hoped to assess the relative variabilities of the different physiological markers and the analysis methods. Methods were based on the crossing of an absolute threshold, on the crossing of a relative threshold, or on fitting a curve to all data points. All methods of calculating circadian phase from plasma melatonin data were less variable than those calculated using CBT or cortisol data. The standard deviation for the phase estimates using CBT data was 0.78 h, using cortisol data was 0.65 h, and for the eight analysis methods using melatonin data was 0.23 to 0.35 h. While the variability for these markers might be different for other subject populations and/or less stringent study conditions, assessment of the intrinsic variability of the different calculations of circadian phase can be applied to allow inference of the statistical significance of phase and phase shift calculations, as well as estimation of sample size or statistical power for the number of subjects within an experimental protocol.
Spectroscopic studies of ionic solvation—XIII. Sodium-23 nuclear magnetic resonance in mixed solvents

Abstract Sodium-23 chemical shifts have been determined in dimethylsulfoxide-acetonitrile, dimethylsulfoxide-nitromethane, pyridine-nitromethane, pyridine-acetonitrile, benzonitrile-nitromethane and pyridine-dimethylsulfoxide binary mixtures. In each case a smooth transition is observed from one pure solvent to the other but the plots show considerable curvature indicating preferential solvation by one of the solvents. The relative solvating abilities of the solvents in binary mixtures were found to be: DMSO > CH3NO2, DMSO > CH3CN, DMSO > Py, Py > CH3CN, PhCN > CH3NO2. Preferential solvation of the sodium ion by DMSO in DMSO-Py mixtures is also confirmed by the far infrared study of the Na+ ion-solvent cage vibration in the binary mixture.
Image enhancement of the in vivo leukocyte-endothelium contact zone using optical sectioning microscopy.

A major determinant of the strength of leukocyte [white blood cell (WBC)] to endothelium [endothelial cell (EC)] adhesion is the contact area formed between the two cells, which is often obscured by out-of-focus information inherent to intravital microscopy. To improve visualization of the WBC-EC contact zone, techniques of optical sectioning microscopy were developed to enhance brightfield images of WBC-EC adhesion in postcapillary venules of the mesentery of the rat. A 50×/1.0 NA objective was held in a piezoelectric mount that was computer-driven, and video images were obtained by digitizing images from a CCD camera while focusing through the vertical direction in 1 μm steps over a depth of 16 μm. Using measurements of the microscope's optical transfer function, deconvolution of the central image was performed in the Fourier domain using the technique of singular value decomposition with Tikhonov-Miller regulation to remove out-of-focus information. Measurement of the length of the WBC-EC contact zone (L C) in the original images yielded values on the order of 4.32±1.08 μm (mean±SD). The enhanced images showed a significantly 35% smallerL C equal to 2.78±0.70 μm. Topical application of the chemoattractant f-met-leu-phe resulted in a 26% increase inL C to 3.49±0.72 μm, thus suggesting that upregulation of adhesion molecules on the WBC membrane results in the recruitment of additional membrane area from surface ruffles into the zone of adhesion. Other advantages of the deconvolution were to visualize structural characteristics of the microvascular wall and parenchymal tissue in greater detail. Thus, brightfield optical sectioning microscopy may provide a valuable tool forin vivo studies of the microvasculature, and serves as a useful alternative to fluorescence microscopy without the undesirable effects of exogenous fluorophores and exposure to ultraviolet radiation.
A sensitive analytical method for the detection and quantitation of adenosine in biological samples.

Abstract A new method for the measurement of adenosine in biological materials has been developed. The method is based on the combined principles of isotope dilution and enzymatic catalysis using a highly specific adenosine kinase isolated from rat heart. By differential centrifugation and gel filtration, this adenosine kinase was obtained free of adenosine deaminase and other enzymes which would have been a source of error in the use of this enzyme in the adenosine assay. The cardiac adenosine kinase was shown to be highly specific and to exhibit an apparent K m for adenosine of 0.35 μ M . Using this enzyme, unknown quantities of adenosine could be detected by measuring the effect of their addition on the conversion of radioisotopic adenosine to 5′-AMP in the kinase reaction. In this procedure, as little as 20 pmoles of adenosine could be detected. To test the applicability of the assay, measurements of the tissue content of this nucleoside were made in samples of dog and rat hearts frozen in situ under control, hypoxic, or ischemic conditions. The assay has several advantageous features when compared to other existing methods used to measure adenosine: a minimum of sample preparation is required before the actual assay procedure; many samples can be processed per day by a single operator; single determinations can be done on as little as 5 μl of sample, and the specificity of the assay can be readily checked by treatment of samples with adenosine deaminase.
Psychotic major depression: a benefit-risk assessment of treatment options.

Numerous studies in the past three decades have characterised ‘psychotic major depression’, a subtype of major depression which is accompanied by delusions or other psychotic features. Evidence from phenomenological and neurobiological investigations indicates that this is a unique disorder with clinical and biological characteristics that are distinct from those of nonpsychotic depression and from other psychotic disorders. Treatment studies have provided evidence of small placebo effects and good responses to electroconvulsive therapy or combination treatment with an antidepressant plus an antipsychotic agent. However, until recently, there were only a few small, prospective, double-blind, controlled trials investigating the efficacy of antidepressant-antipsychotic combination pharmacotherapy, yet this constitutes the currently accepted and most universally applied ‘standard of care’ for psychotic depression. Treatment guidelines have been based largely on uncontrolled investigations of electroconvulsive therapy and studies using tricyclic antidepressants and first-generation antipsychotic drugs, which are not frequently chosen as first-line agents today because of concerns regarding tolerability and risks. However, recent open-label studies and large controlled trials of newer antidepressants and antipsychotics have yielded very divergent results thus far, so that the best treatment approach remains elusive. This review discusses the phenomenology and treatment of psychotic depression with a focus on the benefits and risks of various treatment approaches. Problems with this literature are highlighted, and strategies for future research are suggested.
Multiple impacts of a planar kinematic chain with a granular matter

The theoretical model of a planar kinematic chain with multiple points impacting with a granular matter is studied. The force acting on the links penetrating the granular media is a linear superposition of a static (depth-dependent) resistance force and a dynamic (velocity-dependent) frictional force. A general algorithm for the m impacts for an n planar kinematic chain is presented. The complete solution of a two link chain with two impact points is simulated using different initial impact velocities and different impact geometries. We analyze how rapidly the ends of both links impacting a granular media slow upon collision. For most of the analyzed cases the tips of the kinematic chain under high impact force (higher initial velocity) come to rest faster in a granular matter than the same body under low impact force (lower initial velocity). There are also some exceptions to this rule.
Calcification rates of the massive coral Siderastrea siderea and crustose coralline algae along the Florida Keys (USA) outer-reef tract

Coral reefs are degrading on a global scale, and rates of reef-organism calcification are predicted to decline due to ocean warming and acidification. Systematic measurements of calcification over space and time are necessary to detect change resulting from environmental stressors. We established a network of calcification monitoring stations at four managed reefs along the outer Florida Keys Reef Tract (FKRT) from Miami to the Dry Tortugas. Eighty colonies (in two sequential sets of 40) of the reef-building coral, Siderastrea siderea, were transplanted to fixed apparatus that allowed repetitive detachment for buoyant weighing every 6 months. Algal-recruitment tiles were also deployed during each weighing interval to measure net calcification of the crustose coralline algal (CCA) community. Coral-calcification rates were an order of magnitude greater than those of CCA. Rates of coral calcification were seasonal (summer calcification was 53 % greater than winter), and corals in the Dry Tortugas calcified 48 % faster than those at the other three sites. Linear extension rates were also highest in the Dry Tortugas, whereas percent area of the coral skeletons excavated by bioeroding fauna was lowest. The spatial patterns in net coral calcification revealed here correlate well with Holocene reef thickness along the FKRT and, in part, support the “inimical waters hypothesis” proposed by Ginsburg, Hudson, and Shinn almost 50 yrs ago to explain reef development in this region. Due to the homogeneity in coral-calcification rates among the three main Keys sites, we recommend refinement of this hypothesis and suggest that water-quality variables (e.g., carbonate mineral saturation state, dissolved and particulate organic matter, light attenuation) be monitored alongside calcification in future studies. Our results demonstrate that our calcification monitoring network presents a feasible and worthwhile approach to quantifying potential impacts of ocean acidification, warming, and/or deteriorating water quality on the process of calcification.
Post-translational modifications of pancreatic fluid proteins collected via the endoscopic pancreatic function test (ePFT).

Abstract Background Early diagnosis of chronic pancreatitis by mass spectrometry-based proteomics may result in therapies to retard or modify disease progression. We aimed to identify differences in posttranslational modifications (PTMs) in pancreatic fluid proteins from individuals with chronic pancreatitis (n = 9) and non-pancreatitis controls (n = 9). Methods We collected proteomic data from pancreatic fluid using mass spectrometry techniques. We performed database searches with emphasis on PTMs using ProteinPilot. We compared the frequency of specific PTMs in pancreatic fluid between cohorts and also to those identified in bile, gastroduodenal fluid, urine, and pancreatic duct and stellate cell lysates. Results We identified 97 PTMs in endoscopically-collected pancreatic fluid, of which 11 were identified exclusively in one cohort and 9 others were significantly different in frequency between cohorts. Comparing pancreatic fluid with other specimens revealed differences in specific PTM frequencies, indicating that the identified PTMs were not merely artifacts of sample processing. Conclusions We determined PTMs of proteins extracted from pancreatic fluid which differed in frequency in chronic pancreatitis patients verses controls. Such PTMs may serve as biomarker candidates of chronic pancreatitis upon validation with larger cohorts. The analysis of the PTM profile of pancreatic fluid proteins offers an alternative method to standard protein-based biomarker discovery. Biological significance The early diagnosis of chronic pancreatitis is paramount in developing strategies to modify, retard, or halt disease progression. In the present study, we compared post-transitional modifications (PTMs) of proteins extracted from pancreatic fluid of chronic pancreatitis patients verses a control cohort. With many mass spectrometry-based proteomics workflows aimed to identify and quantify proteins, data for PTMs typically comes gratis, in that such data are collected during protein sequencing and, as such, require only downstream bioinformatics processing. We identified a total of 20 PTMs which were exclusive to or significantly different between cohorts. Upon validation with larger cohorts and enrichment of these PTMs may serve as biomarker candidates of chronic pancreatitis. PTM profiling of pancreatic fluid proteins is complementary to standard protein-based biomarker discovery, and may be readily applied to studies of pancreatic disease. This article is part of a Special Issue entitled: Posttranslational Protein modifications in biology and Medicine.
Seeing the Warburg effect in the developing retina

Proliferating cells of the Xenopus laevis retina facultatively use aerobic glycolysis instead of oxidative phosphorylation. This demonstrates that the metabolic rewiring usually associated with the Warburg effect in tumorigenesis may be a more widespread feature of proliferative metabolism than generally appreciated.
Design for an ideal measuring device

Abstract The Heisenberg uncertainty principle yields a fundamental limit to the accuracy of ordinary measuring techniques. For example, a standard voltmeter applied to the signal V = V1cos(ωt) + V2sin(ωt) must have a noise voltage given by the “standard quantum limit” [1] Δ V 1 = Δ V 2 ≳ Δ V sq 1 (1) where Δ V sq 1 = ( s ʃ B d ω 2π h ω 2 ) 1 2 (2) Z is the impedance of the system, and B is the passband of the voltmeter. We show how to evade this limit by measuring only one phase of the signal, while diverting the noise into the other phase. The noise ΔVl can be greatly reduced, but the uncertainty principle is upheld: ΔV1ΔV2 ≳ ΔV2sq1 (3) We discuss the design of a device having this property, and describe its effect on thermal noise as well as quantum fluctuations. Efforts to demonstrate operation of such a device are underway.