Solid-state and multidimensional solution-state NMR of solid phase extracted and ultrafiltered riverine dissolved organic matter

In this study we used multidimensional solution-state NMR to elucidate the differences in the chemical composition of solid phase extracted and ultrafiltered DOM isolates. DOM was isolated from water sampled from an oligotrophic river, the River Tagliamento (Italy). The recovery of total DOM was up to 42% with both isolation techniques. In addition to 1- and 2-D solution-state NMR, we also applied 1-D solid-state 13C NMR spectroscopy for DOM characterization. 13C NMR spectroscopy only produced broad overlapping resonances, thus allowing a bulk characterization of DOM composition. However, it demonstrated that the bulk chemical composition of the two DOM fractions exhibited minor spatial-temporal changes. The 2-D experiments (TOCSY, HMQC) showed that the solid phase extracted hydrophobic DOM contained predominantly aliphatic esters, ethers, and hydroxyl groups, whereas the ultrafiltered DOM was comprised partially of peptides/protein, with further evidence for a small amount of aliphatic/fatty acid material. Sugars were present in both DOM fractions. The results show the two isolation techniques selected for different suites of compounds within the bulk DOM pool.     

An epidemic of scurvy in Afghanistan: assessment and response

In March 2002, there were reports of a hemorrhagic fever outbreak in western Afghanistan. It was later confirmed that the hemorrhagic symptoms and increased mortality were actually due to scurvy. Most aid workers did not include scurvy in the initial differential diagnosis because it is uncommon throughout the world and has mainly been reported in refugee populations in recent times. A rapid assessment confirmed the cases clinically, estimated a prevalence rate of 6.3% (a severe public health problem), and determined that the attack rates peaked each year in January and February (the end of the winter). Many Afghans have limited dietary diversity due to isolated locations, lengthy winters, the continuing drought of the last four years, asset depletion, and loss of livelihood. After numerous food and fortification options to prevent future outbreaks had been considered, vitamin C tablet supplementation was selected because of the relatively rapid response time as compared with other prevention methods. A three-month course of vitamin C tablets was distributed to 827 villages in at-risk areas. The tablets were acceptable and compliance was good. No cases of scurvy were reported for the winter of 2002-03. The case study from Afghanistan demonstrates that scurvy can occur in nonrefugee or nondisplaced populations; vitamin C supplementation can be an effective prevention strategy; there is an urgent need to develop field-friendly techniques to diagnose micronutrient-deficiency diseases; food-security tools should be used to assess and predict risks of nutritional deficiencies; and the humanitarian community should address prevention of scurvy in outbreak-prone areas.     

Chemical cues identify gender and individuality in Giant pandas (Ailuropoda melanoleuca)

The Giant panda communicates with conspecifics by depositing a mixture of volatile compounds (called scent marks) on trees and rocks. Using mass spectrometry, we identified 951 chemical components from scent glands, urine, vaginal secretions, and scent marks made by pandas. The scent marks of the two genders contained a similar array of chemicals but varied in concentration; specifically, males possessed a significantly greater amount of short chain fatty acids (F(1, 29) = 18.4, P = 0.002). Using stepwise discriminate analysis on the relative proportions of a subset of these chemicals, it was possible to classify gender (94% for males and females) and individuality (81% for males and 91% for females) from scent marks. The power to identify individual males was reduced due to the relatedness of two subjects. By cracking the identity code of Giant panda communication, we show insights into how these animals can match individuals with unique chemical profiles. Since radiocollaring is currently banned in China, the techniques described in this paper give field biologists a new means to identify and track pandas in the wild.     

Isomorphic Implication

We study the isomorphic implication problem for Boolean constraints. We show that this is a natural analog of the subgraph isomorphism problem. We prove that, depending on the set of constraints, this problem is in P, or is NP-complete, or is NP-hard, coNP-hard, and in P_‖^NP. We show how to extend the NP-hardness and coNP-hardness to P_‖^NP-hardness for some cases, and conjecture that this can be done in all cases. Supported in part by grants NSF-CCR-0311021 and DFG VO 630/5-1 and VO 630/5-2. An extended abstract of this paper appears in Proceedings of the 30th International Symposium on Mathematical Foundations of Computer Science (MFCS 2005), pp. 119–130, Springer-Verlag Lecture Notes in Computer Science #3618, August 2005. Work of M. Bauland done in part while visiting CASCI’s Laboratory for Complexity at Rochester Institute of Technology. Work of E. Hemaspaandra done in part while on sabbatical at the University of Rochester.     

Motor sequencing deficits in schizophrenia: A comparison with Parkinson's disease.

Motor abnormalities occur in schizophrenia (SZ) and may arise from striatal dysfunction. This study examined whether the pattern of performance on simple and complex motor abilities in SZ was similar to that of patients with Parkinson's disease (PD). Quantitative tests of speeded movement and motor and cognitive sequencing were used to assess 25 SZ, 16 PD, and 84 normal controls (NCs). Sequencing performance was also examined with motor rigidity taken into account. Compared with the NC group, the SZ and PD groups were impaired on measures of motor rigidity and motor sequencing. With rigidity accounted for, the SZ group was significantly more impaired than the PD group on motor sequencing; cognitive and motor processes contributed to the motor deficit. Cognitive sequencing performance predicted motor sequencing performance in PD but not SZ. Although both SZ and PD resulted in significant motor and cognitive sequencing deficits, the pattern and correlates of these deficits differ, suggesting that the affected neural systems underlying motor deficits in SZ are different from those involved in PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Shouldn't we consider...?": Jury discussions of forbidden topics and effects on damage awards.

The Federal Rules of Evidence prohibit disclosure to civil jurors of information that is arguably related to their decision-making (e.g., that either party is insured). The basis for so-called "blindfolding" is that a jury might be biased by this information to alter its appraisal of the evidence to reach a desired verdict. The purpose of this study was to examine the extent to which mock juries in an automobile negligence case discuss several "silent factors" during deliberation (viz., insurance carried by the parties, the payment of attorneys' fees, and previous settlements between the plaintiff and other defendants) and the effects of such discussion on their compensatory damage award. We presented summaries of the evidence that varied in the severity of the plaintiff's injuries and the reprehensibility of the defendant's conduct. These variables influenced judgments of liability and damage awards. Analysis of the content of jury deliberations regarding damages showed that, although nearly all juries talked about silent factors, the size of their damage awards was unrelated to the frequency of these discussions and that such discussion accounted for only a very small portion of the variance in awards. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The chemistry and physiology of sour taste--a review

ABSTRACT:  Sour taste is the key element in the flavor profile of food acidulants. Understanding the chemistry and physiology of sour taste is critical for efficient control of flavor in the formulation of acid and acidified foods. After a brief introduction to the main applications of food acidulants, several chemical parameters associated with sour taste are discussed. Special emphasis is given to hydrogen ions, protonated (undissociated) acid species, titratable acidity, anions, molar concentration, and physical and chemical properties of organic acids. This article also presents an overview of the physiology of sour taste and proposed theories for the transduction mechanisms for sour taste. The physiology of sour taste perception remains controversial and significant diversity exists among species with regard to cellular schemes used for detection of stimuli. The variety of mechanisms proposed, even within individual species, highlights the complexity of elucidating sour taste transduction. However, recent evidence suggests that at least one specific sour taste receptor protein has been identified.     

Zoning and the Nouveau Poor

The nouveau poor, women heading households, who have experienced a dramatic shift from middle income to low income status due to divorce, widowhood, or abandonment, and who own their own homes in America's suburban and small towns constitute a demographic group whose housing opportunities are limited by certain restrictive zoning practices.

Outmoded regulations, such as those with restrictive definitions of family and age-restrictive zoning regulations and covenants, deny these families the opportunity to enter into housesharing arrangements or to divide their homes into principal and accessory units. Because of these policies, nouveau poor families may find that they cannot continue to live in the communities that they had sought out as ideal places for raising their children. Although restrictive zoning regulations have generally been upheld by the courts, they have at times been successfully attacked. An understanding of the court decisions and their public policy implications will provide guidance for land use officials so they can respond to the housing needs of the nouveau poor.     

Cardiovascular reactivity during social and nonsocial stressors: Do children's personal goals and expressive skills matter?

The relationships between social competence and cardiovascular reactivity were evaluated in 180 children (ages 8-17; 52% female; 53% Caucasian). Participants performed a social task (Social Competence Interview [SCI]) and 2 nonsocial tasks while reactivity measures were obtained. Social competence was coded from SCI audiotapes. Among adolescents, higher scores on the Acceptance-Affiliation subscale were associated with increased heart rate (HR) and blood pressures and with decreased HR variability during the SCI. Among boys, greater Acceptance-Affiliation scores were associated with increased vascular reactivity during the SCI. During the nonsocial tasks, higher Self-Defensiveness and Expressiveness scores were associated with increased cardiac output and stroke volume among African American children. Personal strivings and expressive skills do matter for understanding cardiovascular responses in children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Regression Model for Daily Maximum Stream Temperature

An empirical model is developed to predict daily maximum stream temperatures for the summer period. The model is created using a stepwise linear regression procedure to select significant predictors. The predictive model includes a prediction confidence interval to quantify the uncertainty. The methodology is applied to the Truckee River in California and Nevada. The stepwise procedure selects daily maximum air temperature and average daily flow as the variables to predict maximum daily stream temperature at Reno, Nev. The model is shown to work in a predictive mode by validation using three years of historical data. Using the uncertainty quantification, the amount of required additional flow to meet a target stream temperature with a desired level of confidence is determined.