Distribution by Scientific Domains

Kinds of N

  • acid n
  • active n
  • additional n
  • agent n
  • amino n
  • aminopeptidase n
  • antagonist n
  • antioxidant n
  • appropriate n
  • arbitrary n
  • arylalkylamine n
  • available n
  • bidentate n
  • bifunctional n
  • biomass n
  • bipyridine n
  • case n
  • chiral n
  • complex n
  • compound n
  • containing n
  • corresponding n
  • cosmological n
  • decreased n
  • density n
  • diethyl n
  • different n
  • dimension n
  • ethyl n
  • fertilizer n
  • form n
  • g n
  • group n
  • high n
  • i.e. n
  • increased n
  • independent n
  • index n
  • inhibitor n
  • inorganic n
  • integer n
  • intermolecular n
  • intramolecular n
  • ionic liquid n
  • ketene n
  • kg n
  • large n
  • leaf n
  • length n
  • ligand n
  • linear n
  • liquid n
  • litter n
  • log n
  • low n
  • methyl n
  • mg n
  • microbial biomass n
  • microbial n
  • mineral n
  • motif n
  • n log n
  • new n
  • novel n
  • number n
  • of n
  • one n
  • only n
  • order n
  • organic n
  • parameter n
  • phenylethanolamine n
  • protected n
  • pure n
  • pyridine n
  • racemic n
  • rate n
  • refractive index n
  • serotonin n
  • several n
  • single n
  • size n
  • small n
  • sodium n
  • soil n
  • soluble n
  • specific n
  • stable n
  • strong n
  • substituted n
  • symmetrical n
  • terminal n
  • tissue n
  • total n
  • type n
  • und n
  • urinary n
  • variety of n
  • various n
  • von n

  • Terms modified by N

  • n accumulation
  • n acquisition
  • n addition
  • n application
  • n application rate
  • n assimilation
  • n atom
  • n availability
  • n balance
  • n bond
  • n bond distance
  • n bond length
  • n budget
  • n chain
  • n classification
  • n cluster
  • n cm
  • n coating
  • n compound
  • n concentration
  • n condition
  • n content
  • n cycle
  • n cycling
  • n decreased
  • n demand
  • n deposition
  • n distance
  • n donor
  • n dynamics
  • n effects
  • n engl j med
  • n enrichment
  • n fertilisation
  • n fertilization
  • n fertilizer
  • n film
  • n fixation
  • n flux
  • n form
  • n g
  • n gene
  • n group
  • n groups
  • n hcl
  • n hydrogen bond
  • n ii
  • n immobilization
  • n input
  • n interaction
  • n ion
  • n junction
  • n kg
  • n l
  • n layer
  • n level
  • n ligand
  • n limitation
  • n load
  • n log n
  • n loss
  • n m
  • n matrix
  • n metabolism
  • n microsatellite
  • n mineralization
  • n naoh
  • n node
  • n nutrition
  • n pool
  • n protein
  • n rate
  • n ratio
  • n recovery
  • n release
  • n repeat
  • n retention
  • n solar cell
  • n source
  • n species
  • n stage
  • n staging
  • n status
  • n storage
  • n structure
  • n supply
  • n system
  • n terminus
  • n treatment
  • n unit
  • n uptake
  • n value
  • n vertex

  • Selected Abstracts

    Metric spaces in NMR crystallography

    David M. Grant
    Abstract The anisotropic character of the chemical shift can be measured by experiments that provide shift tensor values and comparing these experimental components, obtained from microcrystalline powders, with 3D nuclear shielding tensor components, calculated with quantum chemistry, yields structural models of the analyzed molecules. The use of a metric tensor for evaluating the mean squared deviations, d2, between two or more tensors provides a statistical way to verify the molecular structure governing the theoretical shielding components. The sensitivity of the method is comparable with diffraction methods for the heavier organic atoms (i.e., C, O, N, etc.) but considerably better for the positions of H atoms. Thus, the method is especially powerful for H-bond structure, the position of water molecules in biomolecular species, and other proton important structural features, etc. Unfortunately, the traditional Cartesian tensor components appear as reducible metric representations and lack the orthogonality of irreducible icosahedral and irreducible spherical tensors, both of which are also easy to normalize. Metrics give weighting factors that carry important statistical significance in a structure determination. Details of the mathematical analysis are presented and examples given to illustrate the reason nuclear magnetic resonance are rapidly assuming an important synergistic relationship with diffraction methods (X-ray, neutron scattering, and high energy synchrotron irradiation). 2009 Wiley Periodicals, Inc.Concepts Magn Reson Part A 34A: 217,237, 2009. [source]

    Communication and conflict in young Mexican students: Messages and attitudes

    Francisco A. Laca
    This study involved a population of young Mexican students (N = 526, ages nine to seventeen). It used U.S. instruments to evaluate these students' attitudes about conflict, communication skills, conflict styles, and conflict management message styles in a Hispanic school environment in order to explore the degree of applicability of these instruments to young Spanish-speaking students and to analyze the relations between these constructs. A model in which attitudes about conflict and communication skills predict the conflict management messages was shown to be signi.cant after the corresponding structural analysis. [source]

    Mediator mentors: Improving school climate, nurturing student disposition

    Pamela S. Lane-Garon
    Mediator Mentors, a collaborative research and service project, was begun by California State University-Fresno faculty and the staff of an elementary school (K,8) in the Central San Joaquin Valley. The purpose of the research was to assess conflict resolution program effects on students (N = 300) and school climate. Cross-age mentoring is an important component of this collaborative project. University students preparing for roles in helping professions served as mentors to elementary students. Impacts on student cognitive and affective perspective taking were assessed and student perceptions of school safety were explored. [source]

    Principles of risk assessment for determining the safety of chemicals: Recent assessment of residual solvents in drugs and di(2-ethylhexyl) phthalate

    Ryuichi Hasegawa
    ABSTRACT Risk assessment of chemicals is essential for the estimation of chemical safety, and animal toxicity data are typically used in the evaluation process, which consists of hazard identification, dose,response assessment, exposure assessment, and risk characterization. Hazard identification entails the collection of all available toxicity data and assessment of toxicity endpoints based on findings for repeated dose toxicity, carcinogenicity or genotoxicity and species-specificity. Once a review is compiled, the allowable lifetime exposure level of a chemical is estimated from a dose,response assessment based on several measures. For non-carcinogens and non-genotoxic carcinogens, the no-observed-adverse-effect-level (NOAEL) is divided by uncertainty factors (e.g. with environmental pollutants) or safety factors (e.g. with food additives) to derive a tolerable daily intake (TDI) or acceptable daily intake (ADI), respectively. These factors include interspecies and individual differences, duration of exposure, quality of data, and nature of toxicity such as carcinogenicity or neurotoxicity. For genotoxic carcinogens, low dose extrapolation is accomplished with mathematical modeling (e.g. linearized multistage model) from the point of departure to obtain exposure levels that will be associated with an excess lifetime cancer risk of a certain level. Data for levels of chemicals in food, water and air, are routinely used for exposure assessment. Finally, risk characterization is performed to ensure that the established ,safe' level of exposure exceeds the estimated level of actual exposure. These principles have led to the evaluation of several existing chemicals. To establish a guideline for residual solvents in medicine, the permitted daily exposure (PDE), equivalent to TDI, of N,N-dimethylformamide was derived on the basis of developmental toxicity (malformation) and of N-methylpyrrolidone on the basis of the developmental neurotoxicity. A TDI for di(2-ethylhexyl)phthalate was derived from assessment of testicular toxicity. [source]

    Infertility observed in female rats treated with N-acetyl-L-cysteine: Histopathological examination of ovarian follicles and recovery of fertility

    Miwa Harada
    ABSTRACT, We previously reported infertility in female rats that received N,acetyl-L-cysteine (NAC) intravenously at a dosage of 1000 mg/kg/day. Unfertilized oocytes and gestation day 1 and 2 embryos were assessed morphologically, and the results suggested that absence or thinning of the zona pellucida (ZP) is related to infertility. However, the morphological characteristics of oocytes before ovulation and recovery from the effects of NAC were not clarified. In the present study, the ovarian follicles were histopathologi,cally examined and the recovery of reproductive function was evaluated to investigate the effects of NAC. Female Sprague-Dawley rats at 10 weeks of age received NAC intravenously at 1000 mg/kg/day for more than 1 week. Thinning of the ZP was observed in the ovarian follicles in all stages of growth by light microscopy. Outflow of the components of the ZP between the corona radiata and disarrangement of the corona radiata were more pronounced in growing follicles than in large secondary follicles. Similar findings were observed by electron microscopy, and the effects of NAC were limited to the ZP. Infertility and thinning of the ZP were observed in the no,recovery NAC group, but not in the recovery NAC group, in which animals recovered within four estrous cycles after NAC administration. It has been reported that the ZP is expressed by oocytes or by both oocytes and granulosa cells, but no changes were noted in these cells. The present findings suggest that NAC affects the ZP directly and that reproductive function may recover from the effects of NAC. [source]

    Induction of apoptosis by A3 adenosine receptor agonist N6 -(3-iodobenzyl)-adenosine-5,- N -methylcarboxamide in human leukaemia cells: a possible involvement of intracellular mechanism

    ACTA PHYSIOLOGICA, Issue 2 2010
    P. Mlejnek
    Abstract Aim:, The sensitivity of cancer cells which exhibit multi-drug resistance phenotype to A3 adenosine receptor (A3AR) agonist N6 -(3-iodobenzyl)-adenosine-5,- N -methylcarboxamide (IB-MECA) was studied. Methods:, To establish direct relationship between P-glycoprotein (P-gp, ABCB1 and MDR1) expression and IB-MECA induced cell death, a straightforward method for precise estimation of intracellular level of this A3AR agonist was developed. Results:, We subjected three human leukaemia cell lines HL-60, K562 and K562/HHT to treatment with micromolar concentrations of IB-MECA. Although all cell lines used expressed A3AR, there was a large difference in their sensitivity to IB-MECA. While HL-60 and K562 cells were almost equally sensitive, the K562/HHT cells, which exhibit a multi-drug resistance phenotype because of overexpression of P-gp, were significantly more resistant. We found that the intracellular level of IB-MECA in K562/HHT cells was approx. 10 times lower than those in HL-60 or K562 cells. Inhibitors of P-gp, including cyclosporine A (CsA) and verapamil (Vpa), increased the intracellular level of IB-MECA and reversed the resistance of K562/HHT cells to this drug. Accordingly, shRNA-mediated down-regulation of P-gp significantly increased the intracellular level of IB-MECA in K562/HHT cells which simultaneously exhibited reduced resistance to this A3AR agonist. In addition, an in vitro enzyme-based assay provided evidence that IB-MECA might serve as a substrate for P-gp. Conclusion:, Our results suggest that P-gp overexpression prevents cells from IB-MECA induced apoptosis despite the A3AR expression. Pro-apoptotic effect of IB-MECA seemed to strongly depend on its intracellular accumulation rather than on its interaction with A3AR. [source]

    Formaldehyde-releasers: Relationship to formaldehyde contact allergy, Part 2: Metalworking fluids and remainder

    CONTACT DERMATITIS, Issue 3 2010
    Anton De Groot
    We have reviewed formaldehyde-releasers used in metalworking fluids (MWFs) in this and a previous part of a two-part article. These biocides do not appear to be frequent or important sensitizers. Even in highly selected patient groups of metalworkers, mean prevalence rates of sensitivity are low: 0.2% for Tris(hydroxymethyl)nitromethane, 1.6% for tris(N -hydroxyethyl)hexahydrotriazine, 1.9% for Bioban P-1487 and Bioban CS-1246, and 2.8% for Bioban CS-1135. In the case of the Biobans, many reactions may have been irritant. Only N,N,-methylenebis(5-methyloxazolidine) has a fairly high mean score of 4.0% in metalworkers. With the exception of Bioban P-1487, there is a clear relationship between positive patch test reactions to the releasers and formaldehyde sensitivity: 40,70% of reactions to releasers occur in patients sensitive to formaldehyde and may therefore be caused by formaldehyde allergy. There is a lack of reliable data on the clinical relevance of contact allergy to the formaldehyde releasers in MWF. In most studies, no data on relevance were provided and in those that did, relevance was often found for a (very small) minority of the reactions only. Also discussed here are the formaldehyde-releasers MDM hydantoin, methenamine, N -methylolchloracetamide, paraformaldehyde, and Preventol D2. [source]

    FC02.4 Meteorological factors and standard series patch test reactions

    CONTACT DERMATITIS, Issue 3 2004
    Janice Hegewald
    The existence of seasonal patterns to patch test reactions has been described, but with conflicting causal interpretations. The potential seasonality of patch tests may be due to irritation, changes to skin barrier or changes to immunological functions caused by meteorological fluctuations. For example, increased skin irritability due to cold winter weather and low humidity may cause an increase in irritative/doubtful and weak positive (false positive) reactions. To investigate the extent of the association between weather and patch test results, consecutive patients (N = 73691) patch tested with the standard series of the German Contact Dermatitis Research Group (DKG) at German or Austrian IVDK (http://www.ivdk.de) centres were matched with weather data collected at a nearby (30 km radius) weather station. Temperature and absolute humidity (AH) on the day of patch test application and the two preceding days were averaged to represent the environment most likely to have influenced the skin condition at the time of testing. The results of 24 standard series substances were analyzed with multivariate logistic regression. Half of the standard series substances examined, including fragrance mix, nickel sulphate, and formaldehyde, exhibited evidence of a relationship with meteorological conditions. Fragrance mix and p-Phenylene diamine exhibited the strongest evidence of an association to weather, with the odds of the reactions in all three reaction categories (ir/?, +, ++/+++) increasing during winter conditions. Due to the association between weather and patch test reactivity, the potential effect of meteorological conditions should be considered in the interpretation of patch test reactions. [source]

    Molecular recognition of sugars by lanthanide (III) complexes of a conjugate of N, N -bis[2-[bis[2-(1, 1-dimethylethoxy)-2-oxoethyl]amino]ethyl]glycine and phenylboronic acid

    Elisa Battistini
    Abstract A novel conjugate of phenylboronic acid and an Ln(DTPA) derivative, in which the central acetate pendant arm was replaced by the methylamide of L -lysine, was synthesized and characterized. The results of a fit of variable 17O NMR data and a 1H NMRD profile show that the water residence lifetime of the Gd(III) complex (150,ns) is shorter than that of the parent compound Gd(DTPA)2, (303,ns). Furthermore, the data suggest that several water molecules in the second coordination sphere of Gd(III) contribute to the relaxivity of the conjugate. The Ln(III) complexes of this conjugate are highly suitable for molecular recognition of sugars. The interaction with various sugars was investigated by 11B NMR spectroscopy. Thanks to the thiourea function that links the phenylboronic acid targeting vector with the DTPA derivative, the interactions are stronger than that of phenylboronic acid itself. In particular, the interaction with N -propylfructosamine, a model for the glucose residue in glycated human serum albumin (HSA), is very strong. Unfortunately, the complex also shows a rather strong interaction with hexose-free HSA (KA,=,705,,300). Copyright 2007 John Wiley & Sons, Ltd. [source]

    An HPLC/mass spectrometry platform for the development of multimodality contrast agents and targeted therapeutics: prostate-specific membrane antigen small molecule derivatives

    Valerie Humblet
    Abstract The production of disease-targeted agents requires the covalent conjugation of a targeting molecule with a contrast agent or therapeutic, followed by purification of the product to homogeneity. Typical targeting molecules, such as small molecules and peptides, often have high charge-to-mass ratios and/or hydrophobicity. Contrast agents and therapeutics themselves are also diverse, and include lanthanide chelates for MRI, 99mTc chelates for SPECT, 90Y chelates for radiotherapy, 18F derivatives for PET, and heptamethine indocyanines for near-infrared fluorescent optical imaging. We have constructed a general-purpose HPLC/mass spectrometry platform capable of purifying virtually any targeted agent for any modality. The analytical sub-system is composed of a single dual-head pump that directs mobile phase to either a hot cell for the purification of radioactive agents or to an ES-TOF MS for the purification of nonradioactive agents. Nonradioactive agents are also monitored during purification by ELSD, absorbance and fluorescence. The preparative sub-system is composed of columns and procedures that permit rapid scaling from the analytical system. To demonstrate the platform's utility, we describe the preparation of five small molecule derivatives specific for prostate-specific membrane antigen (PSMA): a gadolinium derivative for MRI, indium, rhenium and technetium derivatives for SPECT, and an yttrium derivative for radiotherapy. All five compounds are derived from a highly anionic targeting ligand engineered to have a single nucleophile for N -hydroxysuccinimide-based conjugation. We also describe optimized column/mobile phase combinations and mass spectrometry settings for each class of agent, and discuss strategies for purifying molecules with extreme charge and/or hydrophobicity. Taken together, our study should expedite the development of disease-targeted, multimodality diagnostic and therapeutic agents. Copyright 2006 John Wiley & Sons, Ltd. [source]

    MRI tumor characterization using Gd-GlyMe-DOTA-perfluorooctyl-mannose-conjugate (Gadofluorine M), a protein-avid contrast agent

    Hans-Jrgen Raatschen
    Abstract The rationale and objectives were to define the MRI tumor-characterizing potential of a new protein-avid contrast agent, Gd-GlyMe-DOTA-perfluorooctyl-mannose-conjugate (Gadofluorine M; Schering AG, Berlin, Germany) in a chemically induced tumor model of varying malignancy. Because of the tendency for this agent to form large micelles in water and to bind strongly to hydrophobic sites on proteins, it was hypothesized that patterns of dynamic tumor enhancement could be used to differentiate benign from malignant lesions, to grade the severity of malignancies and to define areas of tumor necrosis. Gadofluorine M, 0.05,mmol,Gd,kg,1, was administered intravenously to 28 anesthetized rats that had developed over 10 months mammary tumors of varying degrees of malignancy as a consequence of intraperitoneal administration of N -ethyl- N -nitrosourea (ENU), 45,250,mg,kg,1. These tumors ranged histologically from benign fibroadenomas to highly undifferentiated adenocarcinomas. Dynamic enhancement data were analyzed kinetically using a two-compartment tumor model to generate estimates of fractional plasma volume (fPV), apparent fractional extracellular volume (fEV*) and an endothelial transfer coefficient (KPS) for this contrast agent. Tumors were examined microscopically for tumor type, degree of malignancy (Scarff,Bloom,Richardson score) and location of necrosis. Eighteen tumor-bearing rats were successfully imaged. MRI data showed an immediate strong and gradually increasing tumor enhancement. KPS and fEV*, but not fPV obtained from tumors correlated significantly (p,<,0.05) with the SBR tumor grade, r,=,0.65 and 0.56, respectively. Estimates for KPS and fEV* but not fPV were significantly lower in a group consisting of benign and low-grade malignant tumors compared with the group of less-differentiated high-grade tumors (1.61,,0.64 vs 3.37,,1.49, p,<,0.01; 0.45,,0.17 vs 0.78,,0.24, p,<,0.01; and 0.076,,0.048 vs 0.121,,0.088, p,=,0.24, respectively). It is concluded that the protein-avid MRI contrast agent Gadofluorine M enhances tumors of varying malignancy depending on the tumor grade, higher contrast agent accumulation for more malignant lesions. The results show potential utility for differentiating benign and low-grade malignant lesions from high-grade cancers. Copyright 2006 John Wiley & Sons, Ltd. [source]

    B2 kinin receptors mediate the Indian red scorpion venom-induced augmentation of visceral reflexes via the nitric oxide cyclic guanosine monophosphate pathway

    ACTA PHYSIOLOGICA, Issue 4 2009
    S. Kanoo
    Abstract Aim:, This study was performed to delineate the kinin (receptor)-dependent pathways in the Indian red scorpion (Mesobuthus tamulus; MBT) venom-induced pulmonary oedema as well as the augmentation of cardio-pulmonary reflexes evoked by phenyldiguanide (PDG). Methods:, In urethane-anaesthetized adult rats, the effect of venom on the PDG reflex responses (blood pressure, heart rate and respiration rate) and the pulmonary water content was ascertained using various antagonists(des- Arg, B1 receptor antagonist; Hoe 140, B2 receptor antagonist; N, -nitro- l -arginine methyl ester (l -NAME), nitric oxide (NO) synthase inhibitor; methylene blue, soluble guanylate cyclase inhibitor; and glibenclamide, K+ATP channel blocker). The effect of phosphodiesterase V inhibitor (sildenafil citrate) on the reflex response and the pulmonary water content was also examined and compared with venom-induced responses. Results:, Intravenous injection of PDG (10 ,g kg,1) evoked apnoea, bradycardia and hypotension lasting >60 s. Exposure to MBT venom (100 ,g kg,1) for 30 min augmented the PDG reflex responses by two times and increased the pulmonary water content, significantly. Hoe 140 blocked the venom-induced responses (augmentation of PDG reflex and increased pulmonary water content) whereas des-Arg did not. l -NAME, methylene blue or glibenclamide also blocked the venom-induced responses. Furthermore, sildenafil citrate (that increases cGMP levels) produced augmentation of PDG reflex response and increased the pulmonary water content as seen with venom. Conclusion:, The results indicate that venom-induced responses involve B2 kinin receptors via the NO-dependent guanylate cyclase-cGMP pathway involving K+ATP channels. [source]

    On the Effective Liapunov Exponent with Increasing Stochasticity for Tokamap

    A. Maluckov
    Abstract The effective Liapunov exponent statistical description of tokamap with increasing stochasticity is numerically developed. As the 2D Hamiltonian mapping, tokamap is characterized by the two Liapunov exponents lx = ,l, , 0, and 2D Liapunov exponent L = 0. The time development of the effective Liapunov exponent Lxe, the number of trajectories with lx > 0, Np, and the statistics of the non-negative Liapunov exponents are numerically considered following the test ensemble of N = 10000 trajectories. The sticking to regular structures in the phase space of tokamap, which is associated with the non-positive Liapunov exponent lx, clearly effects its statistics. Thus, the behavior of the effective Liapunov exponent Lxe may be taken as one of the qualitative measures of the degree of stochasticity for the observed mapping. ( 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Laser plasma plume kinetic spectroscopy of the nitrogen and carbon species

    Z. Zelinger
    Abstract The formation and decay of carbon and nitrogen atoms, CN radicals and C2 molecules were monitored using spatial- and time-resolved emission spectroscopy in a plasma plume formed during laser ablation of a graphite target in nitrogen atmosphere. A simple exponential model was used to explain the effect of the individual chemical reactions and plasma dynamics on the measured kinetic characteristics. The succession of emissions C , N , CN was observed in the time-resolved spectra, supporting the suggestion that the CN radical is formed mainly by the direct reaction C + N , CN or C2 + N2 , 2CN. The formation of CN radical was enhanced by the additional generation of atomic nitrogen through the RF discharge. ( 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Effective radial Liapunov exponent for the radial diffusion of test electrons

    A. Maluckov
    Abstract The radial diffusion of test electrons in the bounded magnetic field region with irregularities is a realization of the magnetic (deterministic) and collisional (statistical) stochasticities. To clarify the development of stochasticities the effective radial Liapunov exponent Ler, the number of the electron trajectories (magnetic field lines) with positive radial Liapunov exponent Np, the distribution of the radial Liapunov exponent, Kolmogorov entropy and 3D Liapunov exponent are calculated numerically. In the absence of collisions the overlapping among magnetic islands (generation of the global stochasticity) is indicated by the qualitative change from negative to positive Ler in the long time limit. The fact that Np < N, where N is the number of test electrons, is the sign of sticking to the magnetic field structures. From the viewpoint of the radial Liapunov exponents both stochasticities manifest similarly. It is shown that the distribution of the radial Liapunov exponents is not the elementary one, except in the region of the extremely frequent collisions and partially destroyed magnetic field. Transition of the radial diffusion from the strange to the standard diffusion [1] is related with neglecting sticking of the electrons to the magnetic field structures by enough frequent collisions. [source]

    Juvenile sex offenders and institutional misconduct: the role of thought psychopathology

    Matt Delisi
    Background,Little is known about the institutional behaviour of incarcerated sex offenders. Aim,To study the relationships between juvenile sex offending, thought psychopathology and institutional misconduct. Method,We applied negative binomial regression and Area Under Curve Receiver Operating Characteristic (AUC-ROC) analyses to self-report and records data from institutionalised delinquents (N = 813) committed to the California Youth Authority to explore the links between sex offending and institutional misconduct, controlling for offender demographics, institution, index offence, and self-reported and official criminal history. Results,Juvenile sex offending was associated with six forms of institutional misconduct (sexual, general and total misconduct as reviewed by parole board) over 12 and 24 months prior to rating. Two measures of thought psychopathology, which were related to psychosis-like thought, were significantly associated with juvenile sex offender status. These constructs did not, however, mediate the independent predictive effects of adolescent sex offending on institutional misconduct. Conclusion,Interventions to help incarcerated young offenders are likely to be particularly important for those with a sex offending history as they are otherwise likely to persist with antisocial behaviours of all kinds within and beyond the institution. Attention to their thought processes may be particularly useful. Copyright 2008 John Wiley & Sons, Ltd. [source]


    CRIMINOLOGY, Issue 3 2009
    The impacts of quarterly adult arrest rates on later male serious delinquency prevalence rates were investigated in Philadelphia police districts (N = 23) over several years using all male delinquents aged 10,15 years who were mandated to more than "straight" probation. An ecological deterrence model expects more arrests to lead to less delinquency later. A community justice or mass incarceration model, the ecological version of general strain theory, and an ecologized version of the procedural justice model, each anticipates more arrests lead to more delinquency later. Investigating quarterly lags from 3 to 24 months between adult arrests and later delinquency, the results showed a time-dependent relationship. Models with short lags showed the negative relationship expected by ecological deterrence theory. Models with lags of about a year and a half showed the positive relationship expected by the other three theories. Indicators needed so future works can gauge the relative merits of each theoretical perspective more accurately are described. The spatial distributions of current and 1920s delinquency rates were compared. [source]


    CRIMINOLOGY, Issue 1 2005
    This paper examines microsocial contexts of violent and nonviolent dispute-related incidents involving gang members. Data consist of reports of field observations of twelve black and eight white youth street gangs in Chicago between 1959 and 1962. Dispute-related incidents (N = 2,637) were classified according to three primary pretexts: normative or order violations, identity attacks and retaliation. Findings show that disputes associated with each of these generally unfolded consistently with expectations based on the extent to which status concerns were likely to be outweighed by such situational constraints as a close relationship between disputants and audience intervention. We suggest that understanding violence in the gang context will be enhanced greatly by further consideration of the microsocial level of explanation and linkages to its macro- and individual-level counterparts. [source]


    Research Summary: Clinicians and researchers have strongly recommended culturally-focused counseling with African-American men arrested for domestic violence. An experimental clinical trial tested the effectiveness of this approach against conventional cognitive-behavioral counseling in all-African-American groups and in racially-mixed groups (N = 501). No significant difference was found in the reassault rate reported by the men's female partners over a 12-month follow-up period (23% overall). During that period, men in the racially-mixed groups were, moreover, half as likely to be rearrested for domestic violence as the men in the culturally-focused groups. The men's level of racial identification did not significantly affect the outcomes of the counseling options. Policy Implications: Simply adding a culturally-focused counseling group to domestic violence programs does not seem in itself to improve outcomes. In the current study, the culturally-focused counseling was an appendage to an existing agency closely linked to the criminal justice system. Culturally-focused counseling may prove to be more effective within community-based organizations tied to local services and supports. [source]


    Research Summary: This study analyzed data on 3,237 offenders placed in 1 of 38 community-based residential programs as part of their parole or other post-release control. Offenders terminated from these programs were matched to, and compared with, a group of offenders (N = 3,237) under parole or other post-release control who were not placed in residential programming. Data on program characteristics and treatment integrity were obtained through staff surveys and interviews with program directors. This information on program characteristics was then related to the treatment effects associated with each program. Policy Implications: Significant and substantial relationships between program characteristics and program effectiveness were noted. This research provides information that is relevant to the development of correctional programs, and it can be used by funding agencies when awarding contracts for services. [source]

    The energetic cost of activation in mouse fast-twitch muscle is the same whether measured using reduced filament overlap or N -benzyl- p -toluenesulphonamide

    ACTA PHYSIOLOGICA, Issue 4 2008
    C. J. Barclay
    Abstract Aim:, Force generation and transmembrane ion pumping account for the majority of energy expended by contracting skeletal muscles. Energy turnover for ion pumping, activation energy turnover (EA), can be determined by measuring the energy turnover when force generation has been inhibited. Most measurements show that activation accounts for 25,40% of isometric energy turnover. It was recently reported that when force generation in mouse fast-twitch muscle was inhibited using N -benzyl- p -toluenesulphonamide (BTS), activation accounted for as much as 80% of total energy turnover during submaximal contractions. The purpose of this study was to compare EA measured by inhibiting force generation by: (1) the conventional method of reducing contractile filament overlap; and (2) pharmacological inhibition using BTS. Methods:, Experiments were performed in vitro using bundles of fibres from mouse fast-twitch extensor digitorum longus (EDL) muscle. Energy turnover was quantified by measuring the heat produced during 1-s maximal and submaximal tetanic contractions at 20 and 30 C. Results:,EA measured using reduced filament overlap was 0.36 0.04 (n = 8) at 20 C and 0.31 0.05 (n = 6) at 30 C. The corresponding values measured using BTS in maximal contractions were 0.46 0.06 and 0.38 0.06 (n = 6 in both cases). There were no significant differences among these values. EA was also no different when measured using BTS in submaximal contractions. Conclusion:, Activation energy turnover is the same whether measured using BTS or reduced filament overlap and accounts for slightly more than one-third of isometric energy turnover in mouse EDL muscle. [source]

    Low temperature powder diffraction and DFT solid state computational study of hydrogen bonding in NH4VO3

    . Smr
    Abstract The crystal structure of NH4VO3 was refined by the geometry optimization done by total energy minimization in solid state using DFT/plane waves approach. The lattice parameters were derived by the Le Bail technique from the low temperature X-ray (40-293 K) and synchrotron (100-293 K) powder diffraction data. The structure is formed by the infinite chains of irregular VO4 tetrahedra running approximately parallel to the c -axis, which are interlinked by the ammonium ions placed between them. The ammonium ions link to the [VO4], chains through one linear, one bifurcated and two trifurcated N-H,O hydrogen bonds. Considering their stability there are six distinct N-H,O hydrogen bonds: two strong with the N-H,O bond angles close to the straight, two medium with the bond angles of 123 and 148 and two very bent (105 and 107) and hence weak hydrogen bonds. There is a reasonable agreement between the energies of the stretching ,(NH) modes estimated using the optimised N,O contact distances and those obtained experimentally. ( 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Agglomeration of NTO on the surface of HMX particles in water-NMP solvent

    Kwang-Joo Kim
    Abstract A sensitive explosive was coated with a less sensitive explosive in order to improve stability while maintaining explosion performance. Agglomeration of 3-nitro-1,2,4-triazole-5-one (NTO) on the surface of cyclotetramethylene tetranitramine (HMX) crystals in water- N -methyl-2-pyrrolidone (NMP) solvent was performed by cooling crystallization. Phenomena for coating by crystallization and agglomeration were studied by in-situ measurement. The agglomeration kinetic for the coating of NTO on HMX crystals was correlated with the 3rd power of the solution supersaturation and the 2nd power of the number of the suspended particles. ( 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Mixed crystal of bis(,2 -N,N-di-n-butyldithiocarbamato-S,S,S,)-bis(N,N-di-n-butyldithiocarbamato-S,S,)-di-zinc(II) and bis(,2 -N,N-di-n-butyldithiopercarbamato-S,O,O,)-bis(N,N-di-n-butyldithiocarbamato-S,S,)-di-zinc(II)

    F. Emmerling
    Abstract The title compounds Zn2[S2CN(n-C4H9)2]41 and Zn2[(S(SO)CN(n-C4H9)2)(S2CN(n-C4H9)2)]23 build mixed crystals in the ratio 0.42: 0.58. Each compound forms dimers, in which the monomer moieties are related via a two-fold axis, coinciding with that of the monoclinic space group C2/c. The lattice parameters are a = 23.581(9), b = 17.112(5), c = 16.372(9) , and , = 128.33(3). ( 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Synthesis and crystal structure investigation of pyridine-2-(3,-mercaptopropanoic acid)- N -oxide

    R. Ramasubramanian
    Abstract Pyridine-2-(3,-mercaptopropanoic acid)- N -oxide (I), is a higher homologue of 1-oxopyridinium-2-thioacetic acid (II) [1]. It crystallizes in monoclinic space group P21 with a = 9.2168(2) , b = 4.1423(2) , c = 11.3904(4) , , = 98.65(2), V = 429.93(3) 3 and Z = 2. The least-squares refinement gave residual index R = 0.024 for 1070 observed reflections. The introduction of an additional methylene group in (II) causes a flip in the carboxylic acid group of (I) that facilitates the molecules to align infinite antiparallel chains through strong C,HO interactions. The molecules are interlinked by O,HO hydrogen bonding across the chains and forming an infinite screw chain along y-direction. The molecular packing is stabilized by O,HO and C,HO hydrogen bonding and ,-, electron interactions. This is an important facet of the crystal packing. ( 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Nitric oxide, superoxide and renal blood flow autoregulation in SHR after perinatal L -arginine and antioxidants

    ACTA PHYSIOLOGICA, Issue 4 2007
    M. P. Koeners
    Abstract Aim:, Nitric oxide (NO) and superoxide are considered to be regulatory in renal blood flow (RBF) autoregulation, and hence may contribute to development of hypertension. To extend our previous observations that dynamic NO release is impaired in the spontaneously hypertensive rat (SHR) we investigated, firstly, if superoxide dependency of RBF autoregulation is increased in SHR and, secondly, if the beneficial effect of perinatal supplementation in SHR is partly as a result of early correction of RBF autoregulation. We hypothesized that perinatal supplementation by restoring dynamic NO release and/or decreasing superoxide dependency and would improve life-long blood pressure regulation. Methods:, Autoregulation was studied using stepwise reductions in renal perfusion pressure in anaesthetized male SHR, SHR perinatally supplemented with arginine and antioxidants (SHRsuppl) and Wistar-Kyoto (WKY), prior to and during i.v. N, -nitro- l -arginine (NO synthase inhibitor) or tempol (superoxide dismutase mimetic). Results:, Spontaneously hypertensive rat displayed a wider operating range of RBF autoregulation as compared with WKY (59 4 vs. 33 2 mmHg, respectively; P < 0.01). Perinatal supplementation in SHR decreased mean arterial pressure, renal vascular resistance and the operating range of RBF autoregulation (43 3 mmHg; P < 0.01). In addition autoregulation efficiency decreased. RBF autoregulation characteristics shifted towards those of normotensive WKY. However, dynamic NO release was still impaired and no clear differences in superoxide dependency in RBF autoregulation between groups was observed. Conclusion:, Perinatal supplements shifted RBF autoregulation characteristics of SHR towards WKY, although capacity of the SHRsuppl kidney to modulate NO production to shear stress still seems impaired. The less strictly controlled RBF as observed in perinatally supplemented SHR could result in an improved long-term blood pressure control. This might partly underlie the beneficial effects of perinatal supplementation. [source]

    Rh(I) and Pd(II) complexes of methoxy functionalized heterocyclic carbene: Synthesis and characterization

    M. E. Gnay
    Abstract A new methoxy functionalized 2-(trichloromethyl)-1,3-diarylimidazolidin (6) was synthesized as the precursor for N-heterocyclic carbene complexes of Pd(II) and Rh(I) by the condensation of N,N'-bis(2,4-dimethoxyphenyl)-1,2-diaminoethane with chloral. The structures of all compounds have been elucidated by a combination of multinuclear NMR spectroscopy, elemental analysis and in one instance, by single crystal X-ray diffraction. Compound 8, C27H34N2O4ClRh, crystallizes in the triclinic space group P-1 with cell dimensions a = 9.7642(12), b = 11.1914(11), c = 13.0102(14), , = 104.034(9), , = 106.658(9), , = 99.658(9) with Z = 2. The molecular structure of 8 shows the geometry around the Rh metal to be a slightly distorted square planar. The crystal structure shows the formation of centrosymmetric dimers via intermolecular C-H...Cl hydrogen bonds. ( 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Crystal structure of 2-(2'-hydroxyphenyl)-6-tributylstannyl-4-(3H )-quinazolinone and 2-(2'-hydroxyphenyl)-6-iodo-4-(3H)-quinazolinone

    Ketai Wang
    Abstract The structures of the title compounds C26H37N2O2Sn (I) and C14H9IN2O2 (II) were determined by single-crystal X-ray diffraction technique. Compound I crystallizes in the triclinic space group P1 with a = 9.560(3) , b = 16.899(6) , c = 17.872(5) , , = 65.957(7), , = 83.603(5), , ( = 75.242(5), V = 2549.8(13) 3, Z = 4, and D =1.374 g/cm3. The compound consists of a quinazolinone ring with phenol and tributylstannyl moieties. Compound II crystallizes in the monoclinic space group P21/c with a = 7.6454(12) , b = 5.9270(9) , c = 27.975(4) ; , = 90, , = 95.081(3), , = 90, V = 1262.7(3) 3, Z = 4, and D = 1.915 g/cm3. The compound consists of a quinazolinone ring with phenol and iodine substituents. For both I and II, the short intramolecular O,H,N and two long intermolecular N,H,O hydrogen bonds are highly effective in holding the molecular system in a stable state. ( 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Crystal structure of a tetrazole derivative

    H. S. Yathirajan
    Abstract 5-(4'-Methyl-1,1'-biphenyl-2-yl)-1H-tetrazole(MBT), C28H24N8, CCDC: 223082, F.W.=472.55, triclinic, P1, a=4.99(1), b=14.25(4), c=16.63(5), , = 90.27(5), , = 91.19(5), , = 90.64(5), V = 1182(6)3, Z = 4, Dcal = 1.327 Mgm -3, , = 0.084mm -1, F000 = 496, , (MoK,) = 0.71073, final R1 and wR2 are 0.0924 and 0.2309, respectively. There are two crystallographically independent molecules in the asymmetric unit. The dihedral angles between the two phenyl rings of the biphenyl ring system are 44.2(2) and 44.3(2) for the two molecules respectively. The molecules are stabilized by N-H,N and C-H,N types of intermolecular hydrogen bonds in the unit cell in addition to van der Waals forces. 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim [source]

    Synthesis and X-ray structure of two conformational isomers of [Zn(medpt)(SCN)2], medpt = bis (3 , aminopropyl)methylamine

    S. Guha
    Abstract Two conformational isomers of [Zn (medpt)(NCS)2], medpt=bis(3-aminopropyl) methylamine, (1) and (2) have been synthesised and the crystal structures are determined using single crystal X-ray diffraction. The structures of the complexes have been solved by Patterson method and refined by full-matrix least- squares techniques to R1 = 0.0524 for (1) and R1 = 0.0506 for (2), respectively. The geometry around the Zn(II) centre in both isomers is distorted trigonal bipyramidal. The two pendent thiocyanate moieties in (1), with Zn,N,C angles 167.9(4),173.9(4), coordinate the mental centre almost linearly while the corresponding coordinations in (2) are significantly bent [Zn,N,C angles 150.8(3),153.1(2)]. Intermolecular N,H,S hydrogen bonds stabilise the crystal packing in the complexes forming infinite chains parallel to the [100] direction. The combinations of molecular chains generate three/two dimensional supramolecular framework in complexes (1) and (2). ( 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]