The aqueous chlorination of (chloro)phenols is one of the best-studied reactions in the environmental literature. Previous researchers have attributed these reactions to two chlorine species: HOCl ...(at circum-neutral and high pH) and H
OCl
(at low pH). In this study, we seek to examine the roles that two largely overlooked chlorine species, Cl
and Cl
O, may play in the chlorination of (chloro)phenols. Solution pH, chloride concentration, and chlorine dose were systematically varied in order to assess the importance of different chlorine species as chlorinating agents. Our findings indicate that chlorination rates at pH < 6 increase substantially when chloride is present, attributed to the formation of Cl
. At pH 6.0 and a chlorine dose representative of drinking water treatment, Cl
O is predicted to have at best a minor impact on chlorination reactions, whereas Cl
may contribute more than 80% to the overall chlorination rate depending on the (chloro)phenol identity and chloride concentration. While it is not possible to preclude H
OCl
as a chlorinating agent, we were able to model our low-pH data by considering Cl
only. Even traces of chloride can generate sufficient Cl
to influence chlorination kinetics, highlighting the role of chloride as a catalyst in chlorination reactions.
Safeners are so-called "inert" constituents of herbicide formulations added to protect crops from the toxic effects of herbicides. We examined the reactivity of three dichloroacetamide safeners and ...12 structural analogues all neutral compounds of the form Cl(2)CXC(═O)NRR'; X = H, Cl; R-groups include alkyl, branched alkyl, n-allyl, and cyclic moieties in one homogeneous and two heterogeneous reductant systems: solutions of Cr(H(2)O)(6)(2+), suspensions of Fe(II)-amended goethite, and suspensions of Fe(II)-amended hematite. Analyses of reaction products indicate each safener can undergo stepwise hydrogenolysis (replacement of chlorine by hydrogen) in each system at near-neutral pH. The first hydrogenolysis step generates compounds similar (in one case, identical) to herbicide active ingredients. Rates of product formation and (when reactions were sufficiently fast) parent loss were quantified; reaction rates in heterogeneous systems spanned 2 orders of magnitude and were strongly influenced by R-group structure. The length of n-alkyl R-groups exerted opposite effects on hydrogenolysis rates in homogeneous versus heterogeneous systems: as R-group size increased, reduction rates in heterogeneous systems increased, whereas reduction rates in the homogeneous system decreased. Branched alkyl R-groups decreased hydrogenolysis rates relative to their straight-chain homologues in both homogeneous and heterogeneous systems. Reaction rates in heterogeneous systems can be described via polyparameter linear free energy relationships employing molecular parameters likely to influence dichloroacetamide adsorption. The propensity of dichloroacetamide safeners to undergo reductive transformations into herbicide-like products challenges their classification as "inert" agrochemical ingredients.
Standard pregnancy intentions measures do not always align with how people approach pregnancy. Studies that have investigated beyond a binary framework found that those with "ambivalent" feelings ...towards pregnancy are less likely to use contraception consistently, but the reasons for this are unclear. We sought to gain a nuanced understanding of pregnancy desires, and how perceptions about pregnancy are associated with contraceptive use.
We used non-probability quota sampling based on sex, age, and geographic region for a web-based survey of heterosexual men and women, aged 21-44 years, who could become pregnant/impregnate and were not currently pregnant (n = 1,477; 51% female). The survey was created using unique items informed by recent literature. Bivariate and multivariable analyses explored relationships between various perceptions about pregnancy with pregnancy desires categorized as: wanting a pregnancy, not wanting a pregnancy, and not trying but would be okay with a pregnancy. We conducted a sub-group analysis of those who were not trying but would be okay with a pregnancy (n = 460), using descriptive statistics to examine how consistent contraceptive use was associated with emotions and beliefs about avoiding pregnancy.
After adjustment, those who felt that pregnancy may not always be avoidable, but instead determined by fate/higher power, or a natural process that happens when it is meant to, were significantly more likely (aOR: 1.83, 95% CI: 1.05-3.36; aOR: 2.21, 95% CI: 1.29-3.76, respectively) to report not trying but being okay with pregnancy, whereas those with negative feelings about a pregnancy were less likely to feel okay about a pregnancy (aOR: 0.11, 95% CI: 0.08-0.15), versus not wanting a pregnancy. In the sub-group analysis, those who felt pregnancy was determined by fate/higher power or a natural process were more likely to report not using contraception consistently (70%, 68%, respectively).
Those who state they are not trying but would be okay with pregnancy may not use contraception consistently because of beliefs that pregnancy is predetermined. Our findings support less categorical and more multidimensional approaches to measuring fertility intentions, with important implications for reproductive health service provision.
Anticipating which pollutants are amenable to treatment by iron-based bimetallic reductants requires an understanding of the mechanism(s) driving pollutant reduction. Here, batch studies with six ...bimetals (Au/Fe, Co/Fe, Cu/Fe, Ni/ Fe, Pd/Fe, and Pt/Fe) and four oxidants (alkyl polyhalides, vinyl polyhalides, alkynes, and water) explored the influence of the electron acceptor on reductant reactivity. Bimetals exhibited disparate reactivity toward some oxidant classes. For example, Pt/Fe enhanced rates of cis-dichloroethylene reduction, but it inhibited the reduction of several alkyl polyhalides. Moreover, the rate increase for vinyl polyhalide reduction by Ni/Fe (approximately 100-fold) and Pd/Fe (approximately 1000-fold) was far greater than that measured for alkyl polyhalides (approximately 10-fold), and reactivity toward vinyl polyhalides exhibited a more pronounced dependence on Ni and Pd loadings than did reactivity toward alkyl polyhalides. These results suggest that the reactions of alkyl and vinyl polyhalides with iron-based bimetals involve different active reductants. Neither rates of alkyl nor vinyl polyhalide reduction correlated with rates of iron corrosion by water, contrary to expectations if galvanic corrosion was primarily responsible for organohalide reduction. Trends observed for the hydrogenation of 2-butyne did mirror the sequence we identified for 1,1,1-trichloroethane reduction, consistent with a role for atomic hydrogen as the principal electron donor in these two systems.
Based on findings from four in-depth case studies within global brand manufacturers in the fast moving consumer goods (fmcg) industry, this paper develops a framework for understanding the ...organisational processes that support consumer co-creation within new product development (NPD). A new perspective, that of co-creation, in which consumers are ‘active’ participants in the design and development of new products, is challenging the traditional model of NPD. Co-creation provides an opportunity for market researchers to develop a people-centric approach to research, thereby humanising the NPD process. Key to co-creation practices are: a culture supporting innovation and co-creation; a strategy for consumer selection; a focus on qualitative research methods; and training in business creativity and relationship-building skills.
Background: Residency training is increasingly occurring in community settings. The opportunity for community-based scholarship is untapped and substantial. We explored Community Family Medicine ...Preceptors’ understanding of Educational Scholarship (ES), looked at barriers and enablers to ES, and identified opportunities to promote the growth of ES in this setting.
Methods: We conducted semi-structured interviews with fifteen purposively chosen community-based Family Medicine preceptors in a distributed Canadian family medicine program.
Results: Community Family Medicine Preceptors strongly self-identify as clinical teachers. They are not well acquainted with the definition of ES, but recognize themselves as scholars. Community Family Medicine Preceptors recognize ES has significant value to themselves, their patients, communities, and learners. Most Community Family Medicine Preceptors were interested and willing to invest in ES, but lack of time and scarcity of primary care research experience were seen as barriers. Research process support and a connection to the academic center were considered enablers. Opportunities to promote the growth of ES include recognition that there are fundamental differences between community and academic sites, the development of a mentorship program, and a process to encourage engagement.
Conclusions: Community Family Medicine Preceptors identify foremost as clinician teachers. They are engaged in and recognize the value of ES to their professional community at large and to their patients and learners. There is a growing commitment to the development of ES in the community
A sensitive yet robust analytical method is presented for the simultaneous determination of 12 human pharmaceuticals (valproic acid, phenytoin, ibuprofen, gabapentin, acetaminophen, gemfibrozil, ...naproxen, ketoprofen, secobarbital, phenobarbital, 5-fluorouracil, and diclofenac) and 6 antiseptics (biosol, biphenylol,
p
-chloro-
m
-cresol,
p
-chloro-
m
-xylenol, chlorophene, and triclosan). The method employs solid-phase extraction (SPE) followed by a novel pentafluorobenzylation using a mixture of acetontrile/water (1/1,
v
/
v
). The method is simple to perform (derivatization can be completed in a single test tube) and eliminates the need for any solvent/SPE cartridge drying or blow-down. It affords excellent resolution, high sensitivity and reproducibility, and freedom from interference even for matrices as complex as untreated sewage. The method was applied to the analysis of sewage samples using 15 isotopically labeled surrogates, which resulted in the detection of 10 of the 12 pharmaceuticals and all of the antiseptics sought. Ten of 15 surrogates were synthesized from pure analytes by a simple H-D exchange reaction employing D
2
O and D
2
SO
4
. Measured recoveries were sensitive to matrix effects and varied substantially among analytes, indicative of the limitations associated with using a single surrogate standard.
Most referrals to palliative care and hospice occur late in the trajectory of the disease although an earlier intervention could decrease patients' symptom distress. The purpose of this study was to ...determine the interval between first palliative care consult (PC1) and death (D) in patients diagnosed with advanced cancer (aCA) at our comprehensive cancer center and if such interval has increased over time.
The study group was 2868 consecutive patients who had their PC1 during a 30-month period. We reviewed the charts for information about demographics, cancer type, date of cancer (CA) diagnosis, aCA diagnosis, PC1, and D. aCA was defined as locally recurrent or metastatic.
One thousand four hundred four patients (49%) were female, 1791 (62%) were less than 65 years old, 2563 (89%) had solid tumors, and 2004 (70%) were white. The median PC1-D, aCA-PC1, aCA-D, and CA-D intervals were 42, 147, 250, and 570 days, respectively. The median PC1-D interval was longer in patients with solid tumors (p < 0.0001), less than 65 years old (p = 0.002), and females (p = 0.004). PC1-D was not affected by ethnicity (p = 0.42). The median PC1-D interval in 5 consecutive half-years was 46, 56, 42, 41, and 34 days, respectively (p = 0.02). The number of PC1 in this period increased from 544 to 654 (20%). The ratio of PC involvement in the aCA-D period (PC1-D/aCA-D) decreased from 0.30 to 0.26 over the 5 half-year periods (p = 0.0004).
The first palliative care consultation to death interval has decreased over time at our center. Education is needed among our referring physicians for earlier access to palliative care. Prospective studies are needed to establish the appropriate timing of the first palliative care consultation.
Despite widespread implementation of zero-valent iron remediation schemes, the manner and order of chemical bond cleavage in iron-mediated organohalide transformations remains imperfectly understood. ...We present insights from carbon isotope fractionation for the dehalogenation of 1,1,2,2-tetrachloroethane (1,1,2,2-TeCA) and 1,1,1-trichloroethane (1,1,1-TCA) by various reactants. Elimination of HCl by OH- gave isotope fractionation in 1,1,2,2-TeCA of Euro = -25.6 per thousand, KIE(c) = 1.02 to 1.03 per carbon center, consistentwith a concerted (E2) mechanism. In contrast, 1,1,1-TCA reduction by Cr(II), Fe(0), and Cu-plated iron (Cu/Fe) resulted in Euro = -13.6 per thousand to -15.8 per thousand indicating the initial involvement of a single C-Cl bond (KIE(c) approximately 1.03). 1,1,2,2-TeCA reduction by Cr(II), Fe(0), and Cu/Fe yielded Euro = -18.7 per thousand, -19.3 per thousand, and -17.0 per thousand, respectively. In the two latter cases, depletion of the minor product TCE by 26 per thousand indicated its formation via nonreductive dehydrohalogenation. The major 1,1,2,2-TeCA reduction products, cis- and trans-DCE, differed by 2.3 per thousand +/- 1.0 per thousand in Cr(II) systems, but were equivalent in Fe(0) and Cu/Fe systems. In contrast, the ratio of cis-DCE to trans-DCE concentration was 2.5 for reduction with Cr(II) and Fe(0), but -3.8 with Cu/Fe. Complementary isotope and concentration data therefore suggest differences in the transition state geometry and/ or reaction intermediates in each reductant system.
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