cssi/SciSciGPT-SciSciNet huggingface dataset:
The Frequency Dependence of the AC Irreversibility Line of some High Temperature Superconductors

Ac inductance techniques are commonly used to determine transition temperatures and magnetization versus temperature for superconductors by measurement of the real part of the sample susceptibility χ′. The imaginary or absorptive component of the susceptibility χ″ can also be measured by these techniques. The latter typically shows a peak versus temperature for high temperature superconductors (HTSC) which decreases in temperature as the strength of an applied dc magnetic field increases. The curve of the temperature of the peak in χ″ versus dc magnetic field is called the irreversibility line IL. The IL is sometimes interpreted as dividing magnetically reversible from nonreversible regions in the H-T phase diagram of a superconductor. The temperature dependence of the IL is dependent upon the frequency of the measuring ac field, sometimes strongly so, and is different for different HTSC materials as well as for different forms of the same compound. In this work data is presented for the IL of a variety of samples of YBaCuO, BiSrCaCuO, and TIBaCaCuO measured over a frequency range of 0.1 to 20kHz in dc magnetic fields up to 400 Oe. The dependence of the IL on measurement frequency, ac field strength, demagnetizing factors, and sample diameter is discussed in terms of superconductive glass/flux lattice melting/thermally activated flux flow theories, with particular emphasis upon the IL low frequency behavior.
The Initial Value Problem for Hyperbolic Homogeneous Equations with Constant Coefficients

The differential equations considered in this chapter shall be of the form $$L\,[u]\, = \,Q\left( {\frac{\partial }{{\partial {x_1}}},...,\frac{\partial }{{\partial {x_n}}},\frac{\partial }{{\partial t}}} \right)u = 0$$ (2.1) where Q(η 1, ...., η n, λ) is a form of degree m in its arguments with constant real coefficients. The Cauchy problem to be solved here consists in finding a solution u of (2.1) satisfying the initial conditions for t = 0.
The highly specific, cell cycle–regulated methyltransferase from Caulobacter crescentus relies on a novel DNA recognition mechanism

Two DNA methyltransferases, Dam and β-class cell cycle–regulated DNA methyltransferase (CcrM), are key mediators of bacterial epigenetics. CcrM from the bacterium Caulobacter crescentus (CcrM C. crescentus, methylates adenine at 5′-GANTC-3′) displays 105–107-fold sequence discrimination against noncognate sequences. However, the underlying recognition mechanism is unclear. Here, CcrM C. crescentus activity was either improved or mildly attenuated with substrates having one to three mismatched bp within or adjacent to the recognition site, but only if the strand undergoing methylation is left unchanged. By comparison, single-mismatched substrates resulted in up to 106-fold losses of activity with α (Dam) and γ-class (M.HhaI) DNA methyltransferases. We found that CcrM C. crescentus has a greatly expanded DNA-interaction surface, covering six nucleotides on the 5′ side and eight nucleotides on the 3′ side of its recognition site. Such a large interface may contribute to the enzyme's high sequence fidelity. CcrM C. crescentus displayed the same sequence discrimination with single-stranded substrates, and a surprisingly large (>107-fold) discrimination against ssRNA was largely due to the presence of two or more riboses within the cognate (DNA) site but not outside the site. Results from C-terminal truncations and point mutants supported our hypothesis that the recently identified C-terminal, 80-residue segment is essential for dsDNA recognition but is not required for single-stranded substrates. CcrM orthologs from Agrobacterium tumefaciens and Brucella abortus share some of these newly discovered features of the C. crescentus enzyme, suggesting that the recognition mechanism is conserved. In summary, CcrM C. crescentus uses a previously unknown DNA recognition mechanism.
The Gift of Volunteering: Relational Implications for Social Inequality and Welfare Distribution in Southern Africa

Foreign aid to southern Africa has triggered the growth of a nonprofit sector that increasingly provides welfare and social support for needy populations. However, largely absent from research on this sector are substantive analyses of the contribution of voluntarism and interpersonal exchange to broader welfare development and social cohesion. This paper employs theories of gift exchange to analyze volunteer practices and localized interpretations of volunteering within the welfare structure of post-colonial Pretoria, South Africa, and Lusaka, Zambia. The analysis of ethnographic data pertaining to within- and between-group volunteering reveals particular patterns of “gifting,” which enable many southern Africans to overcome social divides, to strengthen existing bonds, and to fill gaps in the provision of basic public services. We conclude that volunteering succeeds as a form of welfare distribution precisely because of how actors frame their efforts as a gift—ensuring enduring social-relational dynamics and continued social service delivery.
Probing eumelanin photoprotection using a catechol:quinone heterodimer model system

Eumelanin is a natural pigment with photoprotective and radical scavenging characteristics, which are vital for a multitude of living organisms. However, the molecular mechanisms behind these functions remain obscure, in part because eumelanin is a heterogeneous polymer composed of a complex assortment of structural and chemical domains. Despite uncertainty about its precise structure, the functional units of eumelanin are thought to include quinones in various oxidation states. Here, we investigate the photochemistry of a catechol : o-quinone heterodimer as a model system for uncovering the photoprotective roots of eumelanin. Ultrafast transient absorption measurements in the UV to near-IR spectral regions are used to identify the photochemical processes that follow selective excitation of the o-quinone in the heterodimer using 395 nm light. We find that both singlet and triplet o-quinone excited states induce hydrogen atom transfer from the catechol, forming semiquinone radical pairs that persist beyond 2.5 ns, which is the upper time limit accessible by our instrument. Furthermore, the hydrogen atom transfer reaction was found to occur 1000 times faster via the singlet channel. Excited state pathways such as these may be important in eumelanin, where similar hydrogen-bonded interfaces are believed to exist between catechol and o-quinone functional groups.
Novel CNTFET and Memristor based Unbalanced Ternary Logic Gate

Multi-valued logic (MVL) gates are expected to be the future platforms for the beyond-binary circuits and systems. We propose a novel standard ternary inverter (STI) design based on carbon nanotube FET (CNTFET) and memristor. There have been many approaches like resistive load and multi-threshold designs to implement ternary logic gates. The implementation of the MVL technologies is challenging using the existing standard CMOS technology due to its scaling related issues in the sub-nanoscale regime. For example, the resistive load MVL implementations would consume excessive chip area. One of the advantages of the proposed design is the fact that the threshold voltage of the CNTFET can be adjusted by varying the chirality vector. Memristor behaves like a resistor outside a specific frequency range, and it has the potential to offer significantly lower leakage and power dissipation compared to the conventional resistor. Performance and stability of the proposed design have been compared to the existing CNTFET based design. The proposed STI offers 16.37 times and 65.48 times improvement of the power delay product and 96.28% and 95.43% of improvement of the static noise margin, respectively, compared to the STI designs presented in [4] and [7].
Robot Vision

From the Publisher: This book presents a coherent approach to the fast-moving field of computer vision, using a consistent notation based on a detailed understanding of the image formation process. It covers even the most recent research and will provide a useful and current reference for professionals working in the fields of machine vision, image processing, and pattern recognition. An outgrowth of the author's course at MIT, Robot Vision presents a solid framework for understanding existing work and planning future research. Its coverage includes a great deal of material that is important to engineers applying machine vision methods in the real world. The chapters on binary image processing, for example, help explain and suggest how to improve the many commercial devices now available. And the material on photometric stereo and the extended Gaussian image points the way to what may be the next thrust in commercialization of the results in this area. Chapters in the first part of the book emphasize the development of simple symbolic descriptions from images, while the remaining chapters deal with methods that exploit these descriptions. The final chapter offers a detailed description of how to integrate a vision system into an overall robotics system, in this case one designed to pick parts out of a bin. The many exercises complement and extend the material in the text, and an extensive bibliography will serve as a useful guide to current research. Errata (164k PDF)
Imagining One World

Or Rosenboim’s book is a fascinating journey into the historical origins of globalism, one of the most defining and contentious concepts of the twentieth century. Rosenboim argues that the idea of ...
Clinical Gene Therapy Trials for Pompe Disease

Pompe disease is a metabolic myopathy which leads to severe and progressive weakness due to glycogen storage in striated muscle and neurons. Generalized weakness leads to cardiopulmonary insufficiency and early mortality. The spectrum of disease ranges from a fatal early-onset form to a more slowly progressive intermediate and adult-onset type. The severity of disease depends on the amount of residual acid α-glucosidase (GAA) activity which is determined by the nature of the two mutant alleles. The lack of GAA leads to accumulation of glycogen in lysosomes of neurons and striated muscle (especially skeletal and cardiac muscle). Lysosomal dysfunction and cellular autophagy result in neuronal cell loss over time. Enzyme replacement therapy (ERT) is the only currently approved treatment for Pompe disease; however, ERT does not effectively address the neural deficits; therefore, alternative approaches using gene therapy must be considered. The principal objective of gene therapy in Pompe disease is to increase the intrinsic ability of the cells to produce GAA. A variety of recombinant adeno-associated viral vectors (rAAV) are being studied to complete this task. The efficacy of gene therapy not only depends on the efficiency of the gene therapy agent but also on the host's immune response. The most critical immunological challenges are anti-AAV capsid antibodies and anti-GAA antibodies. In this chapter, we review the current status of AAV-mediated gene therapy for Pompe disease.
Chemistry and applications of cyanoximes and their metal complexes

During the past three decades, considerable research effort has been dedicated to a new class of organic ligands – cyanoximes – which have the general formula NC–C(NOH)-R, where R is an electron-withdrawing group. The presence of the CN group makes cyanoximes ∼10 000 times more acidic and better ligands than other known conventional monoximes and dioximes. Also, in numerous cases, this group provides extra nitrogen donor atoms to support the formation of bridges between metal centres in the obtained coordination polymers. With 36 different R groups, the most abundant is the family of mono-cyanoximes, followed by 7 bis-cyanoximes which include aromatic and aliphatic spacers and, lately, tris-cyanoxime representing a ‘tripod’. The total number of obtained and characterized compounds is 44. These simple, low molecular weight molecules represent a series of new excellent ampolydentate ligands – ‘molecular Lego’, or building blocks – for coordination and organometallic chemistry. Uncomplexed ligands, their alkali metal salts, and metal complexes show a large spectrum of biological activity, ranging from growth regulation in plants and antimicrobial activity, to significant in vitro and in vivo cytotoxicity against human cancers. Currently, there are more than three hundred cyanoxime-based complexes, synthesized and studied using a variety of different spectroscopic methods and X-ray analysis. In this review, the preparation and stereochemistry of cyanoxime ligands, their structures and properties, and the most interesting coordination compounds with a broad spectrum of practical applications are summarized.
Micro-scale characterisation of clay at elevated temperatures

The main objective of this study is to use a suite of micro-scale tests to characterise the temperature effects on high plasticity clay. The unheated clay was examined using X-ray diffraction, fiel...
Very low birth weight preterm infant complications where parenteral nutrition is soy or fish oil-based: A retrospective study in Shanghai.

Background and objectives To examine whether a parenteral mixed lipid emulsion containing fish oil reduces the incidence of cholestasis, retinopathy of prematurity (ROP) and bronchopulmonary dysplasia (BPD) in very low birth weight (VLBW, birth weight Methods and study design This retrospective study was conducted in the neonatal intensive care unit of the Children's Hospital of Fudan University. Patients received either a soybean and medium-chain oil (MCT)-based lipid emulsion (Lipofundin) or a mixed lipid emulsion consisting of soybean oil, medium-chain triglycerides, olive oil, and fish oil (SMOF) as parenteral nutrition. The primary outcomes were cholestasis, ROP and BPD, and the secondary outcomes were necrotizing enterocolitis (NEC) and sepsis. Results A total of 149 premature infants (78 in the soybean oil group and 71 in the fish oil group) were included in this study. Multivariate logistic regression analysis showed that gestational age was associated with the incidence of ROP [odds ratio: 0.446, 95% confidence interval (CI): 0.332-0.576, p Conclusions Both fish oil-containing and soybean oil-based parenteral lipid emulsions are safe and well-tolerated by preterm infants. However, the use of the SMOF lipid emulsion did not significantly reduce the incidence of cholestasis, ROP and BPD in VLBW infants.
Review of Sepsis in Burn Patients in 2020.

Background: Severe burn injury results in substantial damage to the skin, inhibiting its ability to perform as the primary barrier to infection. Additionally, severe burn injury can lead to critical illness and extensive time in the intensive care unit (ICU). These two factors work to increase the risk of sepsis in the burn patient compared with other hospitalized patients. The increased risk of sepsis is compounded by the difficulty of diagnosing sepsis in severely burned patients because the pathophysiology of large burns mimics sepsis, leading to possible delay in diagnosis and initiation of treatment. Methods: A literature review was performed to discuss and review the diagnostic difficulties and criteria used to identify patients with sepsis. Additionally, the most current management of sepsis was reviewed and described in caring for burn patients with sepsis. Results: The incidence of sepsis in patients with more than 20% total body surface area (TBSA) burns is between 3% and 30% and is the most common cause of death in the burn patient, with pneumonia being the most common etiology. Several different diagnostic criteria for diagnosing sepsis in burn patients exist, however, none of these criteria have proven to be superior to clinical diagnosis by an experienced burn surgeon. As with sepsis in other patient populations, prompt diagnosis, initiation of antibiotic agents, and source control remain the standard management of sepsis in the burn patient. Conclusions: Because of the loss of the primary infection barrier function of the skin after a substantial burn injury, this patient population is at increased risk for sepsis. Because of the pathophysiology of burn injuries, diagnosing sepsis in the burn population remains challenging. Understanding the most common etiologies of sepsis in burn patients may help with more expedient diagnosis and initiation of treatment.
A Man of Hydraulics: Henri De Pitot (1695-1771)

The technical biography of Henri de Pitot is presented with emphasis given to novel ideas he introduced in hydraulics at the beginning of the eighteenth century. Chief among the various aspects of hydraulics he was interested in are forces on immersed bodies, fluid resistance in rivers, forces acting on the hull and sails of a ship, theory of the Archimedes' Screw and his famous machine to measure velocity.
Hepatectomy, RFA, and Other Liver Directed Therapies for Treatment of Breast Cancer Liver Metastasis: A Systematic Review

Background The liver is the second most common site of breast cancer metastasis. Liver directed therapies including hepatic resection, radiofrequency ablation (RFA), transarterial chemo- and radioembolization (TACE/TARE), and hepatic arterial infusion (HAI) have been scarcely researched for breast cancer liver metastasis (BCLM). The purpose of this review is to present the known body of literature on these therapies for BCLM. Methods A systematic review was performed with pre-specified search terms using PubMed, MEDLINE, EMBASE, and Cochrane Review resulting in 9,957 results. After review of abstracts and application of exclusion criteria, 51 studies were included in this review. Results Hepatic resection afforded the longest median overall survival (mOS) and 5-year survival (45 mo, 41%) across 23 studies. RFA was presented in six studies with pooled mOS and 5-year survival of 38 mo and 11-33%. Disease burden and tumor size was lower amongst hepatic resection and RFA patients. TACE was presented in eight studies with pooled mOS and 1-year survival of 19.6 mo and 32-88.8%. TARE was presented in 10 studies with pooled mOS and 1-year survival of 11.5 mo and 34.5-86%. TACE and TARE populations were selected for chemo-resistant, unresectable disease. Hepatic arterial infusion was presented in five studies with pooled mOS of 11.3 months. Conclusion Although further studies are necessary to delineate appropriate usage of liver directed therapies in BCLM, small studies suggest hepatic resection and RFA, in well selected patients, can result in prolonged survival. Longitudinal studies with larger cohorts are warranted to further investigate the effectiveness of each modality.
Increased Incidence of COVID-19 Infections Amongst Interpersonal Violence Patients.

OBJECTIVE: To investigate whether any specific acute care surgery patient populations are associated with a higher incidence of COVID-19 infection. BACKGROUND: Acute care providers may be exposed to an increased risk of contracting the COVID-19 infection since many patients present to the emergency department without complete screening measures. However, it is not known which patients present with the highest incidence. METHODS: All acute care surgery (ACS) patients who presented to our level I trauma center between March 19, 2020, and September 20, 2020 and were tested for COVID-19 were included in the study. The patients were divided into two cohorts: COVID positive (+) and COVID negative (-). Patient demographics, type of consultation (emergency general surgery consults [EGS], interpersonal violence trauma consults [IPV], and non-interpersonal violence trauma consults [NIPV]), clinical data and outcomes were analyzed. Univariate and multivariate analyses were used to compare differences between the groups. RESULTS: In total, 2177 patients met inclusion criteria. Of these, 116 were COVID+ (5.3%) and 2061 were COVID- (94.7%). COVID+ patients were more frequently Latinos (64.7% versus 61.7%, P = 0.043) and African Americans (18.1% versus 11.2%, P < 0.001) and less frequently Caucasian (6.0% versus 14.1%, P < 0.001). Asian/Filipino/Pacific Islander (7.8% versus 7.2%, P = 0.059) and Native American/Other/Unknown (3.4% versus 5.8%, P = 0.078) groups showed no statistical difference in COVID incidence. Mortality, hospital and ICU lengths of stay were similar between the groups and across patient populations stratified by the type of consultation. Logistic regression demonstrated higher odds of COVID+ infection amongst IPV patients (OR 2.33, 95% CI 1.62-7.56, P < 0.001) compared to other ACS consultation types. CONCLUSION: Our findings demonstrate that victims of interpersonal violence were more likely positive for COVID-19, while in hospital outcomes were similar between COVID-19 positive and negative patients. LEVEL OF EVIDENCE: Level III, Prognostic and Epidemiological.
The extracellular ATP receptor P2RX7 imprints a pro-memory transcriptional signature in effector CD8+ T cells

Development of central memory (Tcm) and resident memory (Trm) CD8+ T cells, which respectively promote immunity in the circulation and in barrier tissues, is not completely understood. Tcm and Trm cells may arise from common precursors, however their fate-inducing signals are elusive. We found that virus-specific effector CD8+ T cells display heterogeneous expression of the extracellular ATP sensor P2RX7. P2RX7-high expression is confined, at peak effector phase, to CD62L+ memory precursors which preferentially form Tcm cells. Among early effector CD8+ T cells, asymmetrical P2RX7 distribution correlated with distinct transcriptional signatures, with P2RX7-high cells enriched for memory and tissue-residency sets. P2RX7-high early effectors preferentially form both Tcm and Trm cells. Defective Tcm and Trm formation in P2RX7 deficiency is significantly reverted when the transcriptional repressor Zeb2 is ablated. Our study indicates that unequal P2RX7 upregulation in effector CD8+ T cells is a foundational element of the early Tcm/Trm fate.
Assessment of Femoral Torsion on Magnetic Resonance Imaging is More Reliable Using Axial-Oblique Sequences Compared with Standard Axial Slices in Patients with Femoroacetabular Impingement Syndrome.

PURPOSE To determine the agreeability of femoral torsion measurements on axial and oblique axial magnetic resonance imaging (MRI) sequences in patients with femoroacetabular impingement syndrome (FAIS). METHODS Patients who underwent primary hip arthroscopy for FAIS between January 2012 - January 2019 were identified. Inclusion criteria were all patients with an MRI scan containing the pelvis and knee imaging. MRI-based measurements of femoral torsion were performed on axial and oblique-axial slices by two raters and inter- and intra-rater reliability was assessed. Bland Altman plots were constructed to evaluate the agreeability between femoral torsion measurements performed using axial and oblique-axial slices. Bivariate correlation analyses were performed to assess the relationship between measurement methods on each respective scan. A linear regression was performed between measurements performed using axial and oblique-axial sequences. RESULTS A total of 164 patients were included. The mean true-axial and oblique axial femoral torsion were 12.2° ± 9.9° and 11.1° ± 9.2°, respectively. The intra-rater reliability for axial and oblique-axial measurements were 0.993 and 0.997, respectively. The inter-rater reliability for axial and oblique-axial measurements were 0.925 and 0.965, respectively. The number of differences within the limits of agreement for axial and oblique-axial femoral torsion measurements was 58.54%. On Pearson correlation analysis, strong positive correlations were found between oblique-axial measurements at multiple time points (r=0.994, p<0.001) as well as axial measurements at multiple time points (r=0.986, p<0.001). A strong positive correlation was found between axial and oblique-axial measurements (r=0.894, p<0.001). A significant regression equation indicated that for each additional increase in axial femoral torsion, the oblique-axial femoral torsion increased 0.837 (95% CI [0.772-0.901]). CONCLUSIONS Femoral torsion values measured on oblique-axial sequences are smaller than on true-axial sequences. Femoral torsion measurements on axial and oblique-axial MRI sequences exhibit poor agreement. Oblique-axial sequences demonstrated greater measurement consistency at multiple timepoints. When evaluating torsional measurements, it is important to delineate which axial sequence was used, especially in patients with suspected severe femoral antetorsion. Standardization of MRI femoral version protocols within one's practice can ensure more consistent decision-making, especially in patients with suspected femoral antetorsion.
Precise New High-P ⊥ 2 Spin Measurements

I will discuss some experiments which study spin forces in high-P ⊥ 2 proton-proton elastic scattering by using a polarized proton target and sometimes a polarized proton beam. Recall that if both protons are unpolarized then one can only measure the differential elastic cross-section. If either the beam or the target is spin-polarized then one can measure the one-spin parameter A, which is called the analyzing power or the left-right asymmetry. If both the beam and the target are polarized then one can measure two-spin quantities such as Ann, the spin-spin correlation parameter. Recall that Ann, parametrizes the spin-spin force while A measures the spin-orbit force.
Immigration and Social Distrust in the Construction of Welfare Policy Across the American States

Social trust ameliorates collective action problems by allowing multicultural societies to coexist and create more effective and equitable public policies. However, existing research warns that increasing ethnic diversity can undermine levels of social trust, hindering mass support for redistributive policies that empower low-income minority populations. Dramatic demographic shifts, induced by immigration patterns over the past fifty years in America, have increased heterogeneity that theoretically erodes majority support for generous social spending. Specifically, we examine the relationship between state-level social trust and immigrant access to social welfare programs using multi-level regression with poststratification to estimate macro-level attitudes of social trust. We find that macro distrust is significantly associated with strict state-level barriers preventing immigrant access to redistributive social programs. We argue that historical ethnic divisions in heavily African American states, not states with sizable Latino or immigrant populations, have influenced patterns in social trust and undermine immigration inclusion into public welfare systems.
Risks and indications of phenylbutazone: another look.

In 1984 an extensive review of phenylbutazone risks was undertaken by the Food and Drug Administration (FDA). Since that review, new recommendations for the drug's use have been published. Marketed in 1952, phenylbutazone has long been recognized as capable of inducing aplastic anemia. The risk of marrow depression is greatest in elderly females treated for over a month. Overall, the risk does not exceed that of many commonly used drugs (e.g., penicillin, which induces anaphylaxis). Nonetheless, phenylbutazone should not be a drug of first choice and should not be used for minor, self-limited conditions.
Use of the BacT/Alert Blood Culture System for Culture of Sterile Body Fluids Other than Blood

Studies have demonstrated that large-volume culture methods for sterile body fluids other than blood increase recovery compared to traditional plated-medium methods. BacT/Alert is a fully automated blood culture system for detecting bacteremia and fungemia. In this study, we compared culture in BacT/Alert standard aerobic and anaerobic bottles, BacT/Alert FAN aerobic and FAN anaerobic bottles, and culture on routine media for six specimen types, i.e., continuous ambulatory peritoneal dialysate (CAPD), peritoneal, amniotic, pericardial, synovial, and pleural fluids. Specimen volumes were divided equally among the three arms of the study. A total of 1,157 specimens were tested, with 227 significant isolates recovered from 193 specimens. Recovery by method was as follows: standard bottles, 186 of 227 (82%); FAN bottles, 217 of 227 (96%); and routine culture, 184 of 227 (81%). The FAN bottles recovered significantly more gram-positive cocci (P < 0.001), Staphylococcus aureus (P = 0.003), coagulase-negative staphylococci (P = 0.008), gram-negative bacilli (P < 0.001), Enterobacteriaceae (P = 0.005), and total organisms (P < 0.001) than the routine culture. There were no significant differences in recovery between the standard bottles and the routine culture. The FAN aerobic bottle recovered significantly more gram-positive cocci (P < 0.001), S. aureus isolates (P < 0.001), coagulase-negative staphyococci (P = 0.003), and total organisms (P < 0.001) than the standard aerobic bottle, while the FAN anaerobic bottle recovered significantly more gram-positive cocci (P < 0.001), S. aureus isolates (P < 0.001), Enterobacteriaceae (P = 0.03), and total organisms (P < 0.001) than the standard anaerobic bottle. For specific specimen types, significantly more isolates were recovered from the FAN bottles compared to the routine culture for synovial (P < 0.001) and CAPD (P = 0.004) fluids. Overall, the FAN bottles were superior in performance to both the standard bottles and the routine culture for detection of microorganisms from the types of sterile body fluids included in this study.
A simulation study on superparamagnetic nanoparticle based multi-tracer tracking

Superparamagnetic nanoparticles (MNPs) have been utilized in biomedical sensing, detection, therapeutics, and diagnostics due to their unique magnetic response under different driving fields. In this letter, we report a multi-tracer tracking method that uses different kinds of MNPs as magnetic tracers along with two alternating magnetic fields that can be potentially used to build magnetic-based flow cytometry. By applying two driving fields at frequency fH and fL to MNPs, the response signal is measured at the combinatorial frequencies such as fH±2fL (3rd harmonics), fH±4fL (5th harmonics), fH±6fL (7th harmonics), and so on. Each MNP has its own signature of phase and amplitude, and it is possible to differentiate individual MNPs in a mixture. We theoretically demonstrated colorizing up to 4-MNP tracers in one mixture with an error rate lower than 10%. The performance of multi-tracer imaging can be optimized by increasing the driving field frequency, choosing MNPs with higher saturation magnetization, a...
Generating Empirically Optimized Composed Matrix Kernels from MATLAB Prototypes

The development of optimized codes is time-consuming and requires extensive architecture, compiler, and language expertise, therefore, computational scientists are often forced to choose between investing considerable time in tuning code or accepting lower performance. In this paper, we describe the first steps toward a fully automated system for the optimization of the matrix algebra kernels that are a foundational part of many scientific applications. To generate highly optimized code from a high-level MATLAB prototype, we define a three-step approach. To begin, we have developed a compiler that converts a MATLAB script into simple C code. We then use the polyhedral optimization system Pluto to optimize that code for coarse-grained parallelism and locality simultaneously. Finally, we annotate the resulting code with performance-tuning directives and use the empirical performance-tuning system Orio to generate many tuned versions of the same operation using different optimization techniques, such as loop unrolling and memory alignment. Orio performs an automated empirical search to select the best among the multiple optimized code variants. We discuss performance results on two architectures.
Shaping Peasant Political Discourse during the New Economic Policy: The Newspaper Krest'ianskaia Gazeta and the Case of "Vladimir Ia"

The problem of the character and function of a "peasant" newspaper bedeviled the Bolsheviks. The party determined to create local journalistic/political agents to establish contact with the villages and set the boundaries of discourse, thereby insinuating itself into peasant society by forming the poorest peasants into a force to destroy the remnants of the old order, in effect Russian peasant society. The sel 'kory were to be crusaders, indoctrinated in most cases through their experience in the Red Army, crusading in the name of socialism to bring alien western values to the countryside, values that the Communist party believed would no longer be alien to these particular peasants. In April 1926, however, the question of the boundaries of discourse exploded in a series of angry exchanges between a sel 'kor, "Vladimir Ia.", and Mikhail Kalinin, nominal head of state. The party had desired that the peasants organize around concepts and ideas, but those of the party. Such ideas failed when they hit the traditional Russian peasant social structure. The attempt to break the traditional society through mobilizing the sel'kory, the "outs," to destroy the "ins" of kulaks and kulak-influenced local party and government agents appeared to Kalinin as instead threatening to strengthen the traditional society. Vladimir Ia. had to be unmasked as a counterrevolutionary.
Rapid reversed-phase high-performance liquid chromatographic analysis of steroid products

Summary The optimisation of conditions for the application of reversed-phase high-performance liquid chromatography (HPLC) to the analysis of steroid products is discussed. The influence of temperature and flow-rate on column efficiency are described. At 60°, the reduced velocity required to give maximum efficiency, is approximately twice that found at room temperature, allowing faster through-put. ( h v ) curves are reported for 5-μm Spherisorb-ODS and Hypersil-ODS material for corticosteroids at 60°. On-column injection techniques are discussed and data presented, showing that for corticosteroids on-column loop injection can be efficient as septum injection using the techniques described.
Detecting prime numbers via roots of polynomials

It is proved that an integer n?=?2 is a prime (resp., composite) number if and only if there exists exactly one (resp., more than one) nth-degree monic polynomial fwith coefficients in Zn, the ring of integers modulo n, such that each element of Znis a root of f. This classroom note could find use in any introductory course on abstract algebra or elementary number theory.
Regulation of axon growth in vivo by activity-based competition

The sex life of the pathogen Cryptococcus neoformans is rather mysterious. This fungus, which is a common cause of illness in AIDS patients, has two mating types, α and a, yet the vast majority of clinical isolates are of the α type. Sexual congress between the two mating types is necessarily rare, but now the fruiting process, involving α cells only and previously considered strictly mitotic and asexual, is revealed as an unusual form of the sexual cycle. As the α mating type has been linked to virulence, these studies also have implications for the mechanism of pathogenicity. The formation of functional neural networks requires precise regulation of the growth and branching of the terminal arbors of axons, processes known to be influenced by early network electrical activity1,2,3. Here we show that a rule of activity-based competition between neighbouring axons appears to govern the growth and branching of retinal ganglion cell (RGC) axon arbors in the developing optic tectum of zebrafish. Mosaic expression of an exogenous potassium channel or a dominant-negative SNARE protein was used to suppress electrical or neurosecretory activity in subsets of RGC axons. Imaging in vivo showed that these forms of activity suppression strongly inhibit both net growth and the formation of new branches by individually transfected RGC axon arbors. The inhibition is relieved when the activity of nearby ‘competing’ RGC axons is also suppressed. These results therefore identify a new form of activity-based competition rule that might be a key regulator of axon growth and branch initiation.
Note on Pain Reactivity and Family Size

Ss (N = 33) were divided into high, medium and low pain-reactivity subgroups, based on their subjective responses to immersion of their hands in cold (4°C) water. The subgroups were compared for differences in family size and birth order. Ss from smaller families (1 to 3 children) exhibited significantly higher pain reactivity than Ss from larger families (4 or more children).
Paradoxes of Logical Equivalence and Identity

In this paper a principle of substitutivity of logical equivalents salve veritate and a version of Leibniz’s law are formulated and each is shown to cause problems when combined with naive truth theories.
Stereoselective total synthesis of β-2,7,11-Cembratriene-4,6-diol (β-CBT), a tumor inhibitory constituent of tobacco smoke

Abstract β-2,7,11-Cembratriene-4,6-diol (10) was synthesized by a sequence involving stereoselective transformations of the cyclotetradecynone 2.
Thrombin injection versus compression of femoral artery pseudoaneurysms

Abstract Objective: The compression of femoral artery pseudoaneurysms is a time consuming, painful, and sometimes unsuccessful procedure. Thrombin injection has been advocated as a superior alternative. In this study, we compare our experiences with both techniques. Methods: All the records of femoral artery false aneurysms that were treated in the vascular laboratory from January 1996 to April 1999 were retrospectively reviewed. Treatment with ultrasound scan–guided compression was compared with treatment with dilute thrombin injection (100 U/mL). Results: Both groups had similar demographics and aneurysm sizes ( P > .2). Of the pseudoaneursyms, 88% were caused by cardiac catheterization and the others were the results of femoral artery access for cardiac surgery (6%), arteriography (5%), and renal dialysis (1%). Compression was successful in 25 of 40 patients (63%). Nine persistent aneurysms necessitated operation, and six were treated successfully with thrombin injection. Primary thrombin injection successfully obliterated 21 pseudoaneurysms in 23 patients. Overall, 27 of 29 pseudoaneurysms were treated successfully with thrombin injection (93%). Thrombosis occurred within seconds of the thrombin injection and required, on average, 300 units of thrombin (100 to 600 units). The patients who underwent successful compression required an average of 37 minutes of compression (range, 5 to 70 minutes) and required analgesia on several occasions. No patients in the thrombin group required analgesia or sedation. Neither group had complications. A cost analysis shows that thrombin treatment results in considerable savings in vascular laboratory resource use but not in overall hospital expenditures. Conclusion: Ultrasound scan–guided thrombin injection is a safe, fast, and painless procedure that completely obliterates femoral artery pseudoaneurysms. The shift from compressive therapy to thrombin injection reduces vascular laboratory use and is less expensive, although it does not significantly impact hospital costs. (J Vasc Surg 1999;30:1052-9.)
Control of Patient Response to Anesthesia using ℒ 1 Adaptive Methods

Abstract In this paper, we discuss the use of recently developed ℒ 1 -adaptive control methods for closed-loop control of anesthesia delivery during surgery. Our main objectives are the design of feedback controllers ensuring that the patient's Bispectral Index profile tracks a prespecified reference trajectory whilst maintaining adherence of vital signs within safe ranges, and demonstrating robustness to inter-patient variability. The controllers are designed from identification-based models constructed from clinical trial data. Simulation results are provided demonstrating the effectiveness of the control methods.
Scattering from finite array of microstrip patches on uniaxial substrate

The problem of plane wave scattering by a finite size array of rectangular microstrip patches printed on a uniaxially anisotropic substrate is considered. Computed radar cross-section data for microstrip patch antenna arrays are presented as a function of array size, incident signal frequency, and anisotropy.
Hybrid Silicon Organic RCE LED for Optical Interconnects and Optical Communications Using Specialized Conductive Adhesives

An RCE-infrared organic light emitting diode was fabricated using silicon as the anode and cathode. The erbium tris(8-hydroxyquinole) emission layer was vacuum-deposited and the device was formed using unidirectional customized conductive adhesives in different configurations.
Leaching dynamics of uranium in a contaminated soil site

Samples from a potentially contaminated industrial area were analyzed for uranium using neutron activation analysis (NAA). Uranium concentration values had a typical uncertainty of 2 % and a detection limit of 1 Bq/kg. To investigate the potential leaching dynamics into ground water two techniques were employed. The US EPA Toxicity Characterization Leaching Procedure (TCLP) and the Sequential Extraction Procedure (SEP) were used to determine the concentration of uranium in the leachates. TCLP and SEP showed that very little of the uranium leached into solution under different chemical conditions. Values of uranium leachates ranged from 0.05 to 3.5 Bq/L; a concentration much lower than the results found in the soil concentrations which ranged from 29 to 155 Bq/kg. NAA showed an 8 % uncertainty for leachates with a detection limit of 0.13 Bq/L. To mimic environmental conditions and acid rain, pH 4.3 water was used as the extraction solvent instead of the acetic acid routinely used in TCLP. Results confirmed that very low amounts of uranium leached with values ranging from 0.0002 to 0.0122 Bq/L. These values represent 0.01–1 % of the uranium in the soil samples. The distribution of uranium in soil according to particle size was also investigated to evaluate its potential movement and possible contamination of the water table. Particles below 250 μm in diameter showed a linear increase in uranium concentration whereas those with a larger diameter had constant uranium content.
Evaluating dispersion in gel permeation chromatography I. Theoretical analysis

Abstract Dispersion (peak spreading, zone broadening) in gel permeation chromatography (GPC) results from a variety of mechanisms, largely independent and additive in their effects. Among the more important of these, in addition to instrumental contributions, is expected to be eddy diffusion within the chromatographic columns. An experimental approach to the study of dispersion in GPC is proposed, based on existing theories and concepts from gas chromatography and liquid—liquid dispersion in packed beds.
50 ways to be a FOSSer: simple ways to involve students & faculty (abstract only)

Participating in free and open source software (FOSS) has numerous benefits for students (and faculty), and there is increasing interest in encouraging such participation. There is a broad range of possible contributions to FOSS projects including documentation, testing, coding, and more. This range allows people with a variety of backgrounds, including little or no CS background, to contribute to a FOSS project. This poster describes the status of a project to identify and categorize learning activities that contribute to FOSS. During Spring 2011, an NSF-sponsored workshop on student participation in humanitarian FOSS for the SoftHum project brought together a group of experienced FOSS developers, faculty, and students. One result of this workshop was a list of nearly 100 learning activities that could contribute to FOSS projects and provide meaningful experiences for students and faculty. We were surprised by the variety of results. Some of the activities have been used successfully or are variations of familiar learning activities; others are ideas that seem promising but require further development and validation. We are experimenting with individual activities, and seeking colleagues interested in doing likewise. We are also mapping the learning activities onto Computer Science Curriculum 2008 to make it easier for faculty to identify relevant activities and map them to course or program learning objectives. The poster briefly summarizes relevant background, describe the process used to identify appropriate activities and provide examples of activities and their mappings.
Fabrication and Manipulation of Ionotropic Hydrogels Crosslinked by Paramagnetic Ions.

This article describes the fabrication and manipulation of millimeter-scale spheres fabricated from ionotropic hydrogels that are cross-linked with paramagnetic metal ions (e.g., Ho 3+ ). These ionotropic hydrogels experience a force in a magnetic field gradient that correlates with the concentration of the paramagnetic cations cross-linking the polymer. In an externally applied magnetic field, the paramagnetic hydrogel spheres assemble into ordered arrays or confined geometrical structures in the regions of highest magnetic field. These spheres can be separated from heterogeneous mixtures of diamagnetic materials using a simple bar magnet. Two applications using these recoverable hydrogel spheres were demonstrated: (i) When prepared with embedded indicator dyes bound to paper, the spheres were used as colorimetric sensors for pH. (ii) When prepared with embedded activated carbon powder, they were used to remove organic materials from aqueous solutions.
Hexagonal Mesoporous Germanium

The blending of mesoporosity with the properties of semiconductors promises new types of multifunctional nanomaterials. It would be particularly interesting to combine the shape selectivity of a mesoporous oxide with the electronic and photonic characteristics of a useful semiconductor. We demonstrated the synthesis of a mesoporous germanium semiconductor using liquid-crystals-templated chemistry. The template removal was achieved by a two-step ion-exchange thermal procedure. This semiconductive mesoporous form of germanium possesses hexagonal pore ordering with very high surface area and exhibits strongly size-dependent optical properties as well as photoluminescence.
Dynamics and energetics of single-step hole transport in DNA hairpins.

The dynamics of single-step hole transport processes have been investigated in a number of DNA conjugates possessing a stilbenedicarboxamide electron acceptor, a guanine primary donor, and several secondary donors. Rate constants for both forward and return hole transport between the primary and secondary donor are obtained from kinetic modeling of the nanosecond transient absorption decay profiles of the stilbene anion radical. The kinetic model requires that the hole be localized on either the primary or the secondary donor and not delocalized over both the primary and the secondary donor. Rate constants for hole transport are found to be dependent upon the identity of the secondary donor, the intervening bases, and the location of the secondary donor in the same strand as the primary donor or in the complementary strand. Rate constants for hole transport are much slower than those for the superexchange process used to inject the hole on the primary donor. This difference is attributed to the larger sol...
The ultra-violet and visible spectra of some halogenoacetatoamminecobalt (III) complexes

The ultra-violet and visible spectra of a series of halogenoacetatopentammine, cis-bis-(halogenoacetato)tetrammine and cis-bis(halogenoacetato)bis(ethylenediamine)cobalt(III) complexes were examined. It was determined that, as the basicity of the various halogenoacetato ligands decreases, its position in the Fajans-Tsuchida spectrochemical series shifts to a shorter wavelength. Also, their relative positions are given in the hyperchromic series.