cssi/SciSciGPT-SciSciNet huggingface dataset:
Glycemia and cognitive function in older adults using glucose-lowering drugs.

Objectives: In experimental studies, both high and low levels of plasma glucose are associated with cognitive impairment. In populations, less is known about the relationship between glycemia and cognitive function, especially in persons using glucose-lowering drugs. Design: A cross-sectional study of 378 high-functioning black and white men and women aged 70 to 79 participating in the Health, Aging, and Body Composition Study (Health ABC) who used glucose-lowering medications. Glycemic measures included fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c). Cognitive function was assessed using the Modified Mini-Mental State Examination (3MS) and the Digit Symbol Substitution Test (DSS) at the same examination visit in which the glycemic measures were determined. Setting: Memphis, Tennessee and Pittsburgh, Pennsylvania. Results: We observed an "inverted-U" relationship (p =.0025 for 3MS, p=.0277 for DSS) between FPG (range 47 - 366 mg/dl) and performance on these two tests. The fasting plasma glucose levels associated with the highest score on the 3MS was 180 mg/dl and 135 mg/dl for the DSS. There was a monotonic inverse relationship between HbAlc and performance on 3MS and DSS without evidence of a threshold effect. Conclusion: Our findings suggest that older adults who are treated for diabetes may experience a small degree of cognitive impairment within the recommended fasting glucose levels, yet measures of long-term glycemic control support tight glycemic control. Given the high prevalence of diabetes and the common use of glucose-lowering drugs in older adults, further studies are needed to elucidate these relationships.
Sympathetic Vibrations: The Atom in Resonant Fields

Science, according to the articulate writer and Nobel Laureate in medicine, Peter Medawar, is the “art of the soluble” [1], and as there is virtually no system in nature that is exactly soluble, the application to the real world of physics—the quintessential science—is to a great extent the art of modeling. To recount the great successes of physics is in large measure to unfold an historical record of aptly chosen, albeit hypothetical, models of reality such as frictionless free-fall, point electrical charges, and ideal gases. Among these immensely useful abstractions is the two-level quantum system.
A Millimeter-Wave Partially Overlapped Beamforming-MIMO Receiver: Theory, Design, and Implementation

This paper presents an analysis and design of a partially overlapped beamforming-multiple-input multiple-output (MIMO) architecture capable of achieving higher beamforming and spatial multiplexing gains with lower number of elements compared to conventional architectures. As a proof of concept, a four-element beamforming-MIMO receiver (RX) covering 64-67-GHz frequency band (the FCC’s newly allocated 64–71-GHz frequency band for high-speed wireless links between small cells) enabling two-stream concurrent reception is designed and measured. By partitioning the RX elements into two clusters and partially overlapping these clusters to create two three-element beamformers, both phased array (coherent beamforming) as well as MIMO (spatial multiplexing) features are simultaneously acquired. 6-bit phase shifters with 360° phase control and 5-bit VGAs with 11-dB range are designed to enable steering of the two RX clusters toward two arbitrary angular locations corresponding to two users. Fabricated in a 130-nm SiGe BiCMOS process, the RX achieves a 30.15-dB maximum direct conversion gain and a 9.8-dB minimum noise figure across 548-MHz IF bandwidth. S-parameter-based array factor measurements verify spatial filtering of the interference and spatial multiplexing in this RX chip.
Lifelong choline supplementation ameliorates Alzheimer's disease pathology and associated cognitive deficits by attenuating microglia activation.

Currently, there are no effective therapies to ameliorate the pathological progression of Alzheimer's disease (AD). Evidence suggests that environmental factors may contribute to AD. Notably, dietary nutrients are suggested to play a key role in mediating mechanisms associated with brain function. Choline is a B-like vitamin nutrient found in common foods that is important in various cell functions. It serves as a methyl donor and as a precursor for production of cell membranes. Choline is also the precursor for acetylcholine, a neurotransmitter which activates the alpha7 nicotinic acetylcholine receptor (α7nAchR), and also acts as an agonist for the Sigma-1 R (σ1R). These receptors regulate CNS immune response, and their dysregulation contributes to AD pathogenesis. Here, we tested whether dietary choline supplementation throughout life reduces AD-like pathology and rescues memory deficits in the APP/PS1 mouse model of AD. We exposed female APP/PS1 and NonTg mice to either a control choline (1.1 g/kg choline chloride) or a choline-supplemented diet (5.0 g/kg choline chloride) from 2.5 to 10 months of age. Mice were tested in the Morris water maze to assess spatial memory followed by neuropathological evaluation. Lifelong choline supplementation significantly reduced amyloid-β plaque load and improved spatial memory in APP/PS1 mice. Mechanistically, these changes were linked to a decrease of the amyloidogenic processing of APP, reductions in disease-associated microglial activation, and a downregulation of the α7nAch and σ1 receptors. Our results demonstrate that lifelong choline supplementation produces profound benefits and suggest that simply modifying diet throughout life may reduce AD pathology.
Reconsidering emotion socialization research using case studies of naturally-occurring parent–child interaction

ABSTRACTThis paper examines emotion socialization in naturally-occurring interaction between parents and children as a situated and negotiated interaction process. While previous research has prima...
Leveraging the Best of Package and IC Design for System Enablement

We find ourselves firmly in the middle of two different design domains, or at least at a point between two new design domains we were not expecting. Where once package design capabilities and flows were derived from PCB design, we find ourselves squarely between IC design and traditional package design. As SoCs (System-on-Chips) have lost favor as the primary system design enablement vehicle, dimensions have shrunk, system designers focus on de-aggregating their chips to their logical subcomponents manufactured in optimal materials and nodes, we find system designers in a new “middle point”, leveraging the best of IC Package and IC design. Package designers now find themselves in the forefront of system-level design and implementation. Once “system design” was done at the SoC silicon level; packaging is now, arguably, the design domain that enables advanced system design. Designers have many different flows and capabilities at their disposal; based on the interconnect dimensions and the materials available, leveraging the capabilities of what has classically been IC design in advanced packaging is becoming more and more prevalent. Package designers are leveraging IC design flows, manufacturing checks and sign off mechanisms to design the next generation of systems. Silicon-based interconnect at silicon process dimensions has become one more vehicle at the disposal of the advanced package designer. Designers can leverage classic flows and design capability available in the IC design space along with their existing package design capabilities. Being able to drive these flows with tools that can work together, as well as additional tools that can act as the system planner or connectivity manager across these domains gives the designer a definite advantage. Designers who are looking for the next generation of EDA tools to support these design challenges will find themselves working with tools available from both the package and IC design space. We propose that users looking to complete these advanced designs will need to leverage capabilities from both design domains, and complete the design using the best tools in each category. Likewise, users may need a single point of entry and design capture at the system level, as well as the capability to manage the overall connectivity across the entire hierarchy of the design. Flows based on these tools can be created to enable and optimize complex designs and meet physical, signal integrity, cost and performance requirements. This paper will the discus the challenges and requirements for working in the space in between these classic design domains, and how they these capabilities can enable advanced package design going forward.
Role of autophagy in alcohol and drug-induced liver injury

Alcohol-related liver disease (ALD) and drug-induced liver injury (DILI) are common causes of severe liver disease, and successful treatments are lacking. Autophagy plays a protective role in both ALD and DILI by selectively removing damaged mitochondria (mitophagy), lipid droplets (lipophagy), protein aggregates and adducts in hepatocytes. Autophagy also protects against ALD by degrading interferon regulatory factor 1 (IRF1) and damaged mitochondria in hepatic macrophages. Specifically, we will discuss selective autophagy for removal of damaged mitochondria and lipid droplets in hepatocytes and autophagy-mediated degradation of IRF1 in hepatic macrophages as protective mechanisms against alcohol-induced liver injury and steatosis. In addition, selective autophagy for removal of damaged mitochondria and protein adducts for protection against DILI is discussed in this review. Development of new therapeutics for ALD and DILI is greatly needed, and selective autophagy pathways may provide promising targets. Drug and alcohol effects on autophagy regulation as well as protective mechanisms of autophagy against DILI and ALD are highlighted in this review.
From working on recovery to working in recovery: Employment status among a nationally representative U.S. sample of individuals who have resolved a significant alcohol or other drug problem.

Abstract Alcohol and other drug (AOD) use disorders exact a prodigious annual economic toll in the United States (U.S.), driven largely by lost productivity due to illness-related absenteeism, underemployment, and unemployment. While recovery from AOD disorders is associated with improved health and functioning, little is known specifically about increases in productivity due to new or resumed employment and who may continue to struggle. Also, because employment can buffer relapse risk by providing structure, meaning, purpose, and income, greater knowledge in this regard would inform relapse prevention efforts as well as employment-related policy. We conducted a cross-sectional, nationally representative survey of the U.S. adult population assessing persons who reported having resolved an AOD problem (n = 2002). Weighted employment, unemployment, retirement, and disability statistics were compared to the general U.S. population. Logistic and linear regression models tested for differences in employment and unemployment among demographic categories and measures of well-being. Compared to the general U.S. population, individuals who had resolved an AOD problem were less likely to be employed or retired, and more likely to be unemployed and disabled. Certain recovering subgroups, including those identifying as black and those with histories of multiple arrests, were further disadvantaged. Conversely, certain factors, such as a higher level of education and less prior criminal justice involvement were associated with lower unemployment risk. Despite being in recovery from an AOD problem, individuals continue to struggle with obtaining employment, particularly black Americans and those with prior criminal histories. Given the importance of employment in addiction recovery and relapse prevention, more research is needed to identify employment barriers so that they can be effectively addressed.
Micro-Acoustic Quad Circulator with Self-Interference Cancellation

In this paper, a micro-acoustic RF circulator with novel “quad” configuration is reported. Four micro-acoustic filters are periodically modulated by RF switches to break the reciprocity. The use of high-Q micro-acoustic filters significantly reduces the modulation frequency (14 MHz) compared to previous demonstrations based on transmission lines (e.g., 333 MHz in [1]). The low modulation frequency translates to an ultra-low power consumption (202 uW, 3600 times smaller than [1]) and one of the highest linearity ( $\mathrm{P}1\mathrm{dB}=31\ \mathrm{dBm}$ ) reported for magnet-free circulators. Furthermore, compared to the more conventional differential configuration, this quad configuration shows advantages in terms of intermodulation products (IMPs) suppression for all the in-band IMPs, guaranteeing a pseudo-linear-time-invariant (pseudo-LTI) operation. Furthermore, the isolation of the circulator is further improved by an additional cancellation circuit, achieving more than 50 dB of isolation in a 10MHz bandwidth (BW). This high level of isolation enables the use of this magnet-free circulator in full-duplex radio, which requires large level of self-interference suppression between the transmitter and the receiver nodes.
Laser Speckle Micro-rheology for biomechanical mapping of breast carcinoma

We introduce a novel technology, termed laser speckle micro-rheology (LSM) that offers the unique capability to map the viscoelastic properties of the tissue microenvironment. This innovation will provide important insight into mechano-biology of disease progression.
Berberine chloride is an alphavirus inhibitor that targets nucleocapsid assembly

Alphaviruses are enveloped positive-sense RNA viruses that can cause serious human illnesses such as polyarthritis and encephalitis. Despite their widespread distribution and medical importance, there are no licensed vaccines or antivirals to combat alphavirus infections. Berberine chloride (BBC) is a pan-alphavirus inhibitor that was previously identified in a replicon-based small-molecule screen. This work showed that BBC inhibits alphavirus replication but also suggested that BBC might have additional effects later in the viral life cycle. Here, we show that BBC has late effects that target the virus nucleocapsid (NC) core. Infected cells treated with BBC late in infection were unable to form stable cytoplasmic NCs or assembly intermediates, as assayed by gradient sedimentation. In vitro studies with recombinant capsid protein (Cp) and purified genomic RNA (gRNA) showed that BBC perturbs core-like particle formation and potentially traps the assembly process in intermediate states. Particles produced from BBC-treated cells were less infectious, despite efficient particle production and only minor decreases in genome packaging. In addition, BBC treatment of free virus particles strongly decreased alphavirus infectivity. In contrast, the infectivity of the negative-sense RNA virus vesicular stomatitis virus was resistant to BBC treatment of infected cells or free virus. Together, our data indicate that BBC alters alphavirus Cp-gRNA interactions and oligomerization and suggest that this may cause defects in NC assembly and in disassembly during subsequent virus entry. Thus, BBC may be considered a novel alphavirus NC assembly inhibitor.IMPORTANCE The alphavirus chikungunya virus (CHIKV) is an example of an emerging human pathogen with increased and rapid global spread. Although an acute CHIKV infection is rarely fatal, many patients suffer from debilitating chronic arthralgia for years. Antivirals against chikungunya and other alphaviruses have been identified in vitro, but to date none have been shown to be efficacious and have been licensed for human use. Here, we investigated a small molecule, berberine chloride (BBC), and showed that it inhibited infectious virus production by several alphaviruses including CHIKV. BBC acted on a late step in the alphavirus exit pathway, namely the formation of the nucleocapsid containing the infectious viral RNA. Better understanding of nucleocapsid formation and its inhibition by BBC will provide important information on the mechanisms of infectious alphavirus production and may enable their future targeting in antiviral strategies.
Neutron total cross section measurement on /sup 140/Ce

A high resolution neutron time-of-flight experiment for neutron energies 20 < or = E < or = 240 keV was carried out on the target nucleus /sup 140/Ce(0/sup +/). The measurement employed a 7.5 nsec beam burst and 250 m flight path. A multilevel shape analysis of the resonance data was performed. The plot of ..sigma..GAMMA/sub n//sup 0/ vs E for the l = 0 J/sup ..pi../ = 1/2/sup +/ levels exhibited a significant change in slope at approx. 160 keV and gives support to the doorway state picture of compound nucleus formation. The observed number of l = 0 levels vs E showed an abrupt increased at 160 keV, the energy at which S/sub 0/ also changed. Various statistical tests were applied to see if this was an effect of missing weak levels but a definite conclusion could not be reached. The behavior of the p wave strength function vs energy was found to be suggestive of doorway state structure. After correcting for missing levels the ratio of s to p wave level spacings was found to be 3.0; the theoretical prediction of 2.9 (for sigma = 4.9) is in good agreement with experiment. The average s, p strengthmore » functions and levels spacings are S/sub 0/ = 1.1 x 10/sup -4/, S/sub 1/ = 0.34 +- 0.05 x 10/sup -4/, /sub l/ = 0 = 4.9 keV, /sub l/ = 1 = 1.64 KeV.« less
Abstract S06-04: Telehealth experiences of adolescent and young adult cancer patients and survivors during the COVID-19 pandemic

Purpose: To describe adolescent and young adult (AYA) cancer patients’ and survivors’ experiences with telehealth during the COVID-19 pandemic. Methods: Eligible participants were identified through the Huntsman Intermountain Adolescent and Young Adult Cancer Care Program, which provides age-specific programming and patient navigation to AYA cancer patients and survivors in Utah and surrounding Mountain West states. Participants were emailed an online survey if they were currently age 18 or older and had been diagnosed with cancer between the ages of 15-39 years. We applied descriptive statistics to summarize demographics, comfortability with technology, access to reliable internet connection, and perceived quality of care while using telehealth. Results: AYAs (N=280) were an average of 29.4 years old at survey (range 18-58); 65.2% were female and 82.4% non-Hispanic white. Over half (54.2%) had received cancer treatment since March 2020. All participants reported owning a computer, tablet, and/or smart phone they could use for telehealth appointments. The majority (93.5%) reported almost always or always having a reliable internet connection. AYAs felt most comfortable having a telehealth appointment in their own home (96.4%); only 12.5% felt comfortable using telehealth at work. Since March 2020, (N=183) 65.4% had a health care visit moved to a telehealth platform due to COVID-19. Of those who recently moved to telehealth, 60.1% had an oncology visit, 33.9% had a primary care visit, and 31.1% had a mental health visit. Additionally over one-third (35.2%) reported the quality of their medical care had decreased since moving to telehealth. This was most commonly due to 1) troubles with audio, video, or connecting through telehealth platforms; 2) telehealth visits feeling impersonal; and 3) feeling that providers more easily dismissed or did not fully address their symptoms. Conclusions: Although AYAs are digital natives, over one-third of AYAs feel the quality of their medical care has decreased since moving to telehealth for COVID-19. Further research should explore medical provider training in using telehealth systems and encourage telehealth practices that help AYAs feel more supported and understood. Citation Format: Karely Mann, Austin R. Waters, Perla L. Vaca Lopez, Echo L. Warner, Judy Ou, Heydon Kaddas, Joemy Ramsay, Nicole Ray, Tomoko Tsukamoto, Douglas B. Fair, Joseph M. Letourneau, Mark A. Lewis, David Gill, Lauri Linder, Anne C. Kirchhoff. Telehealth experiences of adolescent and young adult cancer patients and survivors during the COVID-19 pandemic [abstract]. In: Proceedings of the AACR Virtual Meeting: COVID-19 and Cancer; 2021 Feb 3-5. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(6_Suppl):Abstract nr S06-04.
On relaxation spectra in hard polymers

Spectra of relaxation times have been constructed for a fabric-filled and a cord-filled phenolic of commercial type by combining the results of torsion tests on cylindrical specimens over a relatively wide range of strain rates and temperatures. The resulting spectra are not unimodal and extend over thirty to forty orders of magnitude.
Electrocatalytic syngas generation with a redox non-innocent cobalt 2-phosphinobenzenethiolate complex.

A cobalt complex supported by the 2-(diisopropylphosphaneyl)benzenethiol ligand was synthesized and its electronic structure and reactivity were explored. X-ray diffraction studies indicate a square planar geometry around the cobalt center with a trans arrangement of the phosphine ligands. Density functional theory calculations and electronic spectroscopy measurements suggest a mixed metal–ligand orbital character, in analogy to previously studied dithiolene and diselenolene systems. Electrochemical studies in the presence of 1 atm of CO2 and Bronsted acid additives indicate that the cobalt complex generates syngas, a mixture of H2 and CO, with faradaic efficiencies up to >99%. The ratios of H2 : CO generated vary based on the additive. A H2 : CO ratio of ∼3 : 1 is generated when H2O is used as the Bronsted acid additive. Chemical reduction of the complex indicates a distortion towards a tetrahedral geometry, which is rationalized with DFT predictions as attributable to the populations of orbitals with σ*(Co–S) character. A mechanistic scheme is proposed whereby competitive binding between a proton and CO2 dictates selectivity. This study provides insight into the development of a catalytic system incorporating non-innocent ligands with pendant base moieties for electrochemical syngas production.
Smart Technologies and Internet of Things Designed for Aging in Place

One of the challenges accompanying the global rise in aging populations is the increase in demand for care services. With an increase in age, the need for medical support also grows, which may lead to unplanned and frequent visits to the doctor. Recent developments in Smart technologies and the Internet of Things (IoT) will play an important role in designing suitable home healthcare support services for older adults and enable self-care for people as they age at home. The current COVID-19 pandemic has accelerated the push for telehealth technology solutions including remote patient monitoring for senior adults who are medically or socially vulnerable. Remote health services are being promoted as a means of preserving the patient-healthcare provider relationship at times when an in-person visit is not practical or feasible, especially during COVID-19 and beyond. Smart technologies and IoT could potentially improve health outcomes and save lives. This paper will explore issues and challenges in introducing smart technologies and IoT into the homes of older adults, as well as explore features of the technology and potential outcomes that could allow older adults to remain autonomous, independent, safe, and encourage aging in place. The paper also identifies technology gaps and areas for future research.
Effectiveness of a Long-Term, Home-Based Aerobic Exercise Intervention on Slowing the Progression of Parkinson Disease: Design of the Cyclical Lower Extremity Exercise for Parkinson Disease II (CYCLE-II) Study.

Objective Relatively short duration studies have demonstrated that high-intensity aerobic exercise improves aspects of motor and nonmotor function in people with Parkinson disease (PwPD); however, the effectiveness of a long-term exercise intervention on slowing disease progression is unknown. The primary aim of this study is to determine the disease-altering effects of high-intensity aerobic exercise, administered on an upright stationary cycle, on the progression of PD. A secondary aim is to develop a prognostic model for 12-month changes of Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS III) scores of people undergoing the aerobic exercise intervention. Methods This pragmatic, multisite, single-rater blinded randomized controlled trial will be conducted in 2 large, urban, academic medical centers. The exercise intervention will be administered remotely in the homes of 250 participants with mild to moderate idiopathic PD who will be followed for 12 months. Participants will be randomized to (1) home-based aerobic exercise (AE) or (2) usual and customary care (UCC). People in the AE arm will be asked to complete in-home aerobic exercise sessions at 60% to 80% of heart rate reserve 3 times per week for 12 months utilizing a commercially available upright exercise cycle. The UCC group will continue normal activity levels. Daily activity will be monitored for both groups throughout the 12-month study period. The primary outcome, both to assess disease-modifying response to aerobic exercise and for prognostic modeling in the aerobic exercise arm, is 12-month rate of change in MDS-UPDRS III. Clinical and biomechanical measures will also be used to assess upper and lower extremity motor function, and non-motor functions. Impact If long-term aerobic exercise demonstrates disease-modifying capabilities, this study will provide evidence that "Exercise is Medicine" for PwPD. If so, the derived prognostic model will inform a more patient-specific exercise prescription for PwPD and inform expected disease progression.
The Chemical Constitution of Viruses

Publisher Summary This chapter focuses on the chemical constitution of viruses. Viruses are mainly composed of proteins and nucleic acids. The constituent building blocks of proteins are the amino acids, and most of the common amino acids are found in viruses. The analyses of viral proteins have shown that viral proteins are not protamines or histones, but are rather ordinary in composition, being even, in some cases, quite acidic in character. The reactive groups of viruses appear to be essentially the same as those of other proteins—that is, amino, phenolic, indole, guanidino, sulfhydryl, carboxyl, and perhaps aliphatic hydroxyl. Both ribonucleic (RNA) and deoxyribonucleic acids (DNA) are found in viruses. Only RNA has been found in the viruses affecting higher plants, whereas both RNA and DNA, either singly or jointly, have been reported to be present in highly purified preparations of animal viruses. Nucleic acids, largely because of their primary phosphate groups, are customarily regarded as very reactive compounds. However, in viruses, they are chemically inert. A few enzymes may also be found in viruses. Some other miscellaneous constituents of viruses include nucleoproteins, lipids, polysaccharide, copper, biotin, and flavin.
The water supply is fine: decision-maker perceptions of water quantity and supply-side management

Years of research have called for more science to be integrated into water management decisions and for a shift from supply-side to demand-side management; yet, there remains a strong emphasis on supply-side approaches and in many areas limited attention to hydrological data. A survey and interviews with decision-makers in western North Carolina reveal that there is only low-level concern about water quantity, and this drives a continued emphasis on supply-side management and no perceived need for hydrological data. The historical realities of low demand and abundant water have generated a perception of ‘water supply’ as disconnected from physical, hydrological systems and allowed for ad hoc decision-making processes to prevail. The lack of well-established processes may, ironically, provide significant opportunities for employing collaboration among researchers and decision-makers to develop policies and processes that integrate data into making water management decisions and thus prompt increased attention to water demand.
Seasonal changes in sexual activity and serum levels of LH and testosterone in Finnish Landrace and Suffolk rams.

SUMMARY A procedure for assessing sexual activity (libido) in individual rams is described. Mating activity measured by this procedure and serum levels of luteinizing hormone (LH) and testosterone in Finnish Landrace and Suffolk rams was determined at 8-week intervals from October, 1974 through October, 1975. Seasonal changes were observed for serum LH, testosterone and libido index scores. Mating activity in rams was highest for both breeds during the peak breeding season (October) and declined 50% by late spring and summer before it increased the next October. Serum LH concentrations were lowest in May (.54 ng/ml) and increased abruptly in July (>2 ng/ml) when daily photoperiod began to decrease. Serum testosterone concentrations (>6 ng/ml) and mating activity were highest during the October evaluations. Testosterone decreased gradually through the winter months and reached its lowest levels in late March (2.06 ng/ml in Finn rams and 1.01 ng/ml in Suffolk rams). Thereafter, concentrations gradually increased to levels observed the previous fall. A positive correlation (r = .59) between mean testosterone and mating scores collected across months suggested that seasonal fluctuations in serum testosterone influence the sexual behavior of rams. A temporal relationship was not detected between circulating testosterone and
Eye injuries in childhood: demography, etiology, and prevention

A 1-year survey was conducted of all children with eye injuries seen in the Wills Eye Hospital emergency room to determine demographic, etiologic, and prophylactic factors. There were 810 children with ocular trauma. Childhood ocular injuries are frequent, often resulting in serious visual impairment. Many of these injuries are preventable.
Enzymatic ω Oxidation VII. REDUCED DIPHOSPHOPYRIDINE NUCLEOTIDE-RUBREDOXIN REDUCTASE: PROPERTIES AND FUNCTION AS AN ELECTRON CARRIER IN ω HYDROXYLATION

Abstract Fatty acid and alkane hydroxylation in Pseudomonas oleovorans requires three protein components: DPNH-rubredoxin reductase, rubredoxin, and the ω-hydroxylase. Homogeneous preparations of the reductase catalyze electron transfer not only to the rubredoxin of P. oleovorans but also to the lower molecular weight rubredoxins of the anaerobic bacteria, Peptostreptococcus elsdenii, Clostridium pasteurianum, and Desulfovibrio gigas. In contrast, the reductase is inactive with nonheme iron proteins such as spinach ferredoxin, putidaredoxin, and adrenodoxin, all of which contain labile sulfide. The reductase transfers electrons directly to ferricyanide and dichlorophenolindophenol, and indirectly to cytochrome c; the latter reaction is completely dependent upon the presence of rubredoxin. DPNH is highly superior to TPNH as an electron donor. Since two electron equivalents are accepted per mole of reductase, as shown by anaerobic titrations with DPNH or dithionite, and since 1 mole of FAD is present, it is concluded that no active oxidation-reduction group is present other than the flavin. The absorbance noted at long wave lengths when the enzyme is quantitatively reduced by DPNH or by EDTA and light in the presence of DPN, but not when it is reduced by dithionite or by EDTA and light in the absence of DPN, suggests the formation of a charge transfer complex between the reduced flavoprotein and DPN. A stable semiquinone was not formed during the titrations, as judged by the spectral changes observed. An interaction between rubredoxin and the reductase was demonstrated both by spectrophotometric and fluorimetric techniques. Measurements of the decrease in fluorescence of the reductase in the presence of rubredoxin indicated that these components form a complex in a 1:1 ratio; the dissociation constant of the complex was determined to be 2.1 x 10-7 m. The energy of activation of the enzyme-catalyzed reduction of rubredoxin by DPNH was found to be 5400 cal per mole.
Conformational analysis of oxidized peptide fragments of the C-terminal redox center in thioredoxin reductases by NMR spectroscopy.

Vicinal disulfide rings (VDRs) occur when a disulfide bond forms between adjacent cysteine residues in a protein and results in a rare eight-membered ring structure. This eight-membered ring has been found to exist in four major conformations in solution, divided between cis and trans conformers. Some selenoenzymes use a special type of VDR in which selenium replaces sulfur, generating a vicinal selenosulfide ring (VSeSR). Here, we provide evidence that this substitution reduces ring strain, resulting in a strong preference for the trans conformation relative to cis in a VSeSR (cis:trans – 9:91). This was determined by using the ‘γ-gauche effect’, which makes use of both 1H-NMR and two-dimensional (2D) NMR techniques for determining the amide bond conformeric ratio. The presence of selenium in a VSeSR also lowers the dihedral strain energy (DSE) of the selenosulfide bond relative to the disulfide bond of VDRs. While cis amide geometry decreases strain on the amide bond, it increases strain on the scissile disulfide bond of the VDR found in thioredoxin reductase from Drosophila melanogaster (DmTR). We hypothesize that the cis conformation of the VDR is the catalytically competent conformer for thiol/disulfide exchange. This hypothesis was investigated by computing the DSE of VDR and VSeSR conformers, the structure of which was determined by 2D NMR spectroscopy and energy minimization. The computed values of the VDR from DmTR are 16.5 kJ/mol DSE and 14.3 kJ/mol for the C+ and T− conformers, respectively, supporting the hypothesis that the enzyme uses the C+ conformer for thiol/disulfide exchange. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.
Light-scattering and scanning transmission electron microscopic investigation of the hemocyanin of the bivalve, Yoldia limatula (Say).

Abstract 1. 1. The hemocyanin of the bivalve, Yoldia limatula (Say) was found by light-scattering to have a mol wt of 8.0 ± 0.06 × 106. Mass measurements by scanning transmission electron microscopy (STEM) gave a particle mass of 8.25 ± 0.42 × 106 for the native particle and 4.09 ± 0.20 × 106 for the half-molecule. 2. 2. The hemocyanin subunits fully dissociated in 8.0 M urea and 6.0 M GdmCl at pH 8.0, and at pH 11.0, 0.01 M EDTA have mol. wts of 4.38 × 105, 4.22 × 105 and 4.71 × 105, close to one-twentieth of the parent molecular weight of Y. limatula hemocyanin and most gastropod hemocyanins. 3. 3. Analyses of the urea dissociation transitions studied at pH 8.0, 1 × 10−2 M Mg2+, 1 × 10−2 M Ca2+ and pH 8.0, 3 × 10−3 M Ca2+ suggest few hydrophobic amino acid groups, of the order of 10 to 15 at the contact areas of each half-molecule or decamer. 4. 4. The further dissociation of the decamers to dimers and the dimers to monomers indicates the presence of a larger number of amino acid groups of ca 35–40/dimer and 100–120/monomer. 5. 5. This suggests hydrophobic stabilization of the dimer to dimer and monomer to monomer contacts within the decamers, as observed with other molluscan hemocyanins.
Laser-induced fluorescence detection of atmospheric NO(subscript)2 at parts per trillion mixing ratios

A laser-induced fluorescence instrument designed for continuous, autonomous, in situ observations of atmospheric NO2. The instrument sensitivity is 10 parts per trillion (ppt) in 10 seconds of integration (S/N=2) with a detection limit below 1 ppt.
Induction of T4 UDP-GT activity, serum thyroid stimulating hormone, and thyroid follicular cell proliferation in mice treated with microsomal enzyme inducers

The microsomal enzyme inducers phenobarbital (PB), pregnenolone-16 alpha-carbonitrile (PCN), 3-methylcholanthrene (3MC), and Aroclor 1254 (PCB) are known to induce thyroxine (T(4)) glucuronidation and reduce serum T(4) concentrations in rats. Also, microsomal enzyme inducers that increase serum TSH (i.e., PB and PCN) also increase thyroid follicular cell proliferation in rats. Little is known about the effects of these microsomal enzyme inducers on T(4) glucuronidation, serum thyroid hormone concentrations, serum TSH, and thyroid gland growth in mice. Therefore, we tested the hypothesis that microsomal enzyme inducers induce T(4) UDP-GT activity, resulting in reduced serum T(4) concentrations, as well as increased serum TSH and thyroid follicular cell proliferation in mice. B6C3F male mice were fed a control diet or a diet containing PB (600, 1200, 1800, or 2400 ppm), PCN (250, 500, 1000, or 2000 ppm), 3MC (62.5, 125, 250, or 500 ppm), or PCB (10, 30, 100, or 300 ppm) for 21 days. All four inducers increased liver weight and hepatic microsomal UDP-GT activity toward chloramphenicol, alpha-naphthol, and T(4). PB and PCB decreased serum total T(4), but PCN and 3MC did not. Serum thyroid stimulating hormone was markedly increased by PCN and 3MC treatments, and slightly increased by PB and PCB treatments. All four microsomal enzyme inducers dramatically increased thyroid follicular cell proliferation in mice. The findings suggest that PB, PCN, 3MC, and PCB disrupt thyroid hormone homeostasis in mice.
An analytic approximation to the cardinal functions of Gaussian radial basis functions on an infinite lattice

Gaussian radial basis functions (RBFs) have been very useful in computer graphics and for numerical solutions of partial differential equations where these RBFs are defined, on a grid with uniform spacing h, as translates of the ''master'' function @f(x;@a,h)=exp(-[@a^2/h^2]x^2) where @a is a user-choosable constant. Unfortunately, computing the coefficients of @f(x-jh;@a,h) requires solving a linear system with a dense matrix. It would be much more efficient to rearrange the basis functions into the equivalent ''Lagrangian'' or ''cardinal'' basis because the interpolation matrix in the new basis is the identity matrix; the cardinal basis C"j(x;@a,h) is defined by the set of linear combinations of the Gaussians such that C"j(kh)=1 when k=j and C"j(kh)=0 for all integers k j. We show that the cardinal functions for the uniform grid are C"j(x;h,@a)=C(x/h-j;@a) where C(X;@a)~(@a^2/@p)sin(@pX)/sinh(@a^2X). The relative error is only about 4exp([email protected]^2/@a^2) as demonstrated by the explicit second order approximation. It has long been known that the error in a series of Gaussian RBFs does not converge to zero for fixed @a as h->0, but only to an ''error saturation'' proportional to exp([email protected]^2/@a^2). Because the error in our approximation to the master cardinal function C(X;@a) is the square of the error saturation, there is no penalty for using our new approximations to obtain matrix-free interpolating RBF approximations to an arbitrary function f(x). The master cardinal function on a uniform grid in d dimensions is just the direct product of the one-dimensional cardinal functions. Thus in two dimensions C(X,Y;@a)~(@a^4/@p^2)sin(@pX)sin(@pY)/[sinh(@a^2X)sinh(@a^2Y)]. We show that the matrix-free interpolation can be extended to non-uniform grids by a smooth change of coordinates.
Tuning the Effective Work Function of Gold and Silver Using ω-Functionalized Alkanethiols: Varying Surface Composition through Dilution and Choice of Terminal Groups

Thiol-based self-assembled monolayers (SAMs) have been used to tune the effective work function of gold over a range of ca. 1.8 eV via two strategies: (i) the use of ω-functionalized alkanethiols where the tail groups have widely varying electronegativity or (ii) by the creation of two-component SAMs from selected mixtures of methyl-terminated alkanethiols (C16) and alkanethiols fluorinated at the two terminal carbon atoms (C16F2). UV-photoelectron spectroscopy (UPS) was used to monitor changes in effective work function, using shifts in the low kinetic energy edge of these photoemission spectra to quantify the shift in local vacuum level resulting from the interface dipole effect created by the surface modifier. Tail groups on alkanethiol chains varied from −CH3, to −phenyl, −Cl, −Br, and −CF3 or −CF2CF3, which provided a shift in local vacuum level that varied linearly with the calculated molecular dipole moment of the individual modifiers, as observed previously for a more limited range of alkanethiols...
Effects of nutrient enrichment and biochemical composition of diets of Palmaria mollis on growth and condition of Japanese abalone, Haliotis discus hannai and red abalone, Haliotis rufescens

Abstract Two growth experiments were conducted with juvenile red abalone, Haliotis rufescens and Japanese abalone, Haliotis discus hannai. The first experiment was set up to determine if nutrient levels used for co-culture of the Rhodophyte, Pacific dulse (Palmaria mollis) directly affected abalone growth. No significant differences (ANOVA; P=0.117) were found in growth of abalone cultured in either ambient seawater alone or seawater supplemented with different NaNO3 loads (1176, 1765, 2353, and 2942 μM day−1 NO3–N), NaH2PO4 (83.3 μM day−1 PO4−), and a modified version of Guillard and Ryther's [Gran. Can. J. Microbiol. 8, (1962) 229] f medium containing Fe, Zn, Mn, Cu, Mo, and Co. The second experiment was designed to determine the effect of different nutrient levels on the nutritional value of P. mollis when fed to abalone. P. mollis was cultured with different NaNO3 loads (1176, 1765, 2353, and 2942 μM day−1 NO3–N) and NaH2PO4 (83.3 μM day−1 PO4−) in the presence or absence of f medium trace metals (Fe, Zn, Mn, Cu, Mo, and Co). H. discus hannai showed the highest LGR and SGR when fed on P. mollis supplemented with nitrate loads ranging from 1176 to 2353 μM day−1 NO3–N. In contrast, H. rufescens showed the highest linear growth rate (LGR) when fed on P. mollis supplemented with higher nitrate loads of 2353 to 2942 μM day−1 NO3–N, while nitrate load had no significant effect on specific growth rate (SGR). Both abalone species grew better on P. mollis supplied with 0.75f+Zn (day−1) metal solution [Gran. Can. J. Microbiol. 8 (1962) 229] compared to those without trace metal additions, with H. discus hannai showing a further improvement in food conversion efficiencies (FCE). The present work shows that understanding and manipulating the culture environment of P. mollis can significantly affect growth, FCE, and daily food consumption (DFC) of H. discus hannai and H. rufescens.
Frontier Bonds in QM/MM Methods: A Comparison of Different Approaches

A major complication in hybrid QM/MM methods is the treatment of the frontier between the quantum part, describing the reactive region, and the classical part, describing the environment. Two approaches to this problem, the “link atom” method and the “local self-consistent field” (LSCF) formalism, are compared in this paper. For this purpose, the LSCF formalism has been introduced into the CHARMM program. A detailed description of the two approaches is presented. The results of semiempirical calculations of deprotonation enthalpies and proton affinities of propanol and a tripeptide with different treatments of the frontier bond are compared. Particular emphasis is placed on the effect of an external charge. It is shown that the choice of the QM/MM electronic interactions included in the frontier region is of considerable importance in determining the electron distribution of the QM region and the overall energy. The link atom and LSCF methods are generally of similar accuracy if care is taken in the choic...
Study On The High-Voltage Long-Gap Discharge By Using The Image Converter Camera

By using the image converter camera, we studied the high voltage long-gap discharge phenomena, particularly, the process of corona and precursor discharge varying with concerned parameters. Since the sustained and intervals of the precursors are about a few deci-microsecond to a few microsecond, the framing photography might lose signals, the scanning technique with whole vision field has been used. To solve the cynchronizing problem, we have developed a technique which can trigger the camera by means of spark gap-optoelectronic transformation. Some protecting measures are also described in this paper.
In situ steric stabilization of titanium dioxide particles synthesized by a sol-gel process

Abstract Spherical titanium dioxide particles were synthesized via the hydrolysis of tetraethylorthotitanate (TEOT) in ethanol in the presence of hydroxypropyl cellulose (HPC) which served as an in situ steric stabilizer. This work focused on the effect that water concentration had on the HPCTiO 2 interactions leading to steric stabilization. The water concentration varied in the range [H 2 O]/[TEOT] = 5.3–60. The amount of adsorbed HPC increased threefold over this water concentration range. This correlates with measurements of the preferential adsorption of water on TiO 2 in ethanol. The particle size decreased fivefold in the presence of HPC over the range of water concentrations studied owing to the combined effects of increased HPC adsorption and increased nucleation rates. Mean particle diameters as small as 70 nm were obtained.
Cerebral asymmetry in visual attention

The traditional view of cerebral lateralization of various cognitive functions has been challenged by results from recent experimental and clinical studies. Evidence has been gathered to suggest that a seemingly unitized cognitive function can be further broken down into various processing subcomponents which are distributed across the two hemispheres. For instance, according to such a more complex conceptualization of cerebral lateralization, language is seen not as a unitary ability, but rather as a collection of syntactic, semantic, and prosodic components, with each lateralized in particular manners. In much the same way, the present study attempts to examine the cerebral lateralization patterns of the seemingly unitary visual perception process. In a visual half-field experiment, 20 normal subjects were asked to make same/different judgments to laterally presented arrays of stimuli of the same type as previously studied by Treisman and her colleagues in experiments attempting to separate the preattentive and attentive stages of visual perception. Hemispheric differences were obtained only in tasks requiring attentive processing (i.e., Treisman's glueing). Results indicate a local attentional strategy for the left hemisphere and a global attentional strategy for the right hemisphere.