Silver 2,4'-Bipyridine Coordination Polymer for the High-Capacity Trapping of Perrhenate, A Pertechnetate Surrogate.

Pertechnetate, the most stable form of the radionuclide 99Tc in aerobic aqueous systems, is a hazardous anion present in nuclear waste. Its high mobility in water makes the remediation of the anion challenging. In the past decade, significant effort has been placed into finding materials capable of adsorbing this species. Here, we present the synthesis and high-resolution crystal structure of the coordination polymer [Ag(2,4'-bipyridine)]NO3, which is capable of sequestering perrhenate─a pertechnetate surrogate─through anion exchange to form another new coordination polymer, [Ag(2,4'-bipyridine)]ReO4. Both the beginning and end structures were solved by single-crystal X-ray diffraction and the adsorption reaction was monitored through inductively coupled plasma-optical emission spectroscopy and UV-vis spectroscopy. The exchange reaction follows a pseudo-second-order mechanism and the maximum adsorption capacity is 764 mg ReO4/g [Ag(2,4'-bipyridine)]NO3, one of the highest recorded for a coordination polymer or metal-organic framework. A solvent-mediated recrystallization mechanism was determined by monitoring the ion-exchange reaction by scanning electron microscopy-energy-dispersive spectroscopy and powder X-ray diffraction.

The costs and benefits of kindness for kids.

What do children think makes an act kind? Which kind acts are children likely to perform? Previous research with adults suggests that the kindness of acts depends largely on the benefit provided and to a lesser extent on the cost incurred, and that adults are more likely to perform low-cost, high-benefit kind acts. In the current study, children (9-12 years, n = 945) and teens (13-17 years, n = 939) rated the benefit, cost, kindness, and likelihood of performing 173 acts of kindness, and adults (18+ years, n = 891) rated how beneficial, costly, kind, and likely the acts would be for young people to perform. Among children and teens, benefit but not cost predicted the kindness of acts, and benefit positively predicted, but cost negatively predicted, performance (for "kindness quotients" of 61% and 65%, respectively). Among adults, benefit and cost predicted the kindness of acts, and cost, but not benefit, negatively predicted performance (for a kindness quotient of 59%). The results for children and teens are similar to those from previous research with adults; however, adults are more sensitive to cost when rating kindness, are less sensitive to benefit when rating performance by young people, and are less likely to think young people will perform acts of kindness overall. In practical terms, the results suggest that recommending cost-effective acts may be the best way to encourage children to be kinder.

A broader theory of cooperation can better explain "purity".

Self-control provides one cooperative explanation for "purity." Other types of cooperation provide additional explanations. For example, individuals compete for status by displaying high-value social and sexual traits, which are moralised because they reduce the mutual costs of conflict. As this theory predicts, sexually unattractive traits are perceived as morally bad, aside from self-control. Moral psychology will advance more quickly by drawing on all theories of cooperation.

Selective Chromium(VI) Trapping by an Acetate-Releasing Coordination Polymer.

We report the high-capacity and selective uptake of Cr(VI) from water using the coordination polymer silver bipyridine acetate (SBA, [Ag(4,4'-bipy)][CH3CO2]·3H2O). Cr capture involves the release of acetate, and we have structurally characterized two of the product phases that form: silver bipyridine chromate (SBC, SLUG-56, [Ag(4,4'-bipy)][CrO4]0.5·3.5H2O) and silver bipyridine dichromate (SBDC, SLUG-57, [Ag(4,4'-bipy)][Cr2O7]0.5·H2O). SBA maintains a high Cr uptake capacity over a wide range of pH values (2-10), reaching a maximum of 143 mg Cr/g at pH 4. This Cr uptake capacity is one of the highest among coordination polymers. SBA offers the additional benefits of a one-step, room temperature, aqueous synthesis and its release of a non-toxic anion following Cr(VI) capture, acetate. Furthermore, SBA capture of Cr(VI) remains >97% in the presence of a 50-fold molar excess of sulfate, nitrate, or carbonate. We also investigated the Cr(VI) sequestration abilities of silver 1,2-bis(4-pyridyl)ethane nitrate (SEN, [Ag(4,4'-bpe)][NO3]) and structurally characterized the silver 1,2-bis(4-pyridyl)ethane chromate (SEC, SLUG-58, [Ag(4,4'-bpe)][CrO4]0.5) product. SEN was, however, a less effective Cr(VI) sequestering material than SBA.

RATES OF EXUDATIVE RECURRENCE FOR EYES WITH INACTIVATED WET AGE-RELATED MACULAR DEGENERATION ON 12-WEEK INTERVAL DOSING WITH BEVACIZUMAB THERAPY.

PURPOSE: To determine the recurrence rate of exudative age-related macular degeneration (wet AMD) in patients on 12-week dosing interval anti-vascular endothelial growth factor (anti-VEGF) bevacizumab therapy. METHODS: A retrospective chart review was performed on wet AMD patients treated with anti-VEGF therapy using a "treat-and-extend" methodology at one physician's practice site over 2 years (2012-2014). Charts were evaluated for visual acuity, anti-VEGF agent used, treatment interval, duration of treatment, trials off of anti-VEGF therapy, evidence of exudation, and wet AMD recurrence characteristics. RESULTS: Three hundred and twenty-one wet AMD patients were treated. Fifty-seven eyes were without active exudation by clinical examination or optical coherence tomography (OCT) and were maintained on repeating 12-week interval suppressive anti-VEGF therapy. Sixteen percent (8/49) showed exudation recurrence with an average 10% cumulative recurrence rate per year for eyes on bevacizumab. Eight eyes without active exudation were discontinued off of bevacizumab therapy. Sixty-three percent (5/8) demonstrated recurrence on average 4 months after stopping therapy. CONCLUSION: The findings in this study suggest that if a patient can be extended to 12-week interval bevacizumab therapy, there is on average a 10% chance of recurrence with each successive year. If anti-VEGF therapy is discontinued in these patients, there is an increased chance of recurrence by 4 months.

Cross-cultural regularities in the cognitive architecture of pride.

Pride occurs in every known culture, appears early in development, is reliably triggered by achievements and formidability, and causes a characteristic display that is recognized everywhere. Here, we evaluate the theory that pride evolved to guide decisions relevant to pursuing actions that enhance valuation and respect for a person in the minds of others. By hypothesis, pride is a neurocomputational program tailored by selection to orchestrate cognition and behavior in the service of: (i) motivating the cost-effective pursuit of courses of action that would increase others' valuations and respect of the individual, (ii) motivating the advertisement of acts or characteristics whose recognition by others would lead them to enhance their evaluations of the individual, and (iii) mobilizing the individual to take advantage of the resulting enhanced social landscape. To modulate how much to invest in actions that might lead to enhanced evaluations by others, the pride system must forecast the magnitude of the evaluations the action would evoke in the audience and calibrate its activation proportionally. We tested this prediction in 16 countries across 4 continents (n = 2,085), for 25 acts and traits. As predicted, the pride intensity for a given act or trait closely tracks the valuations of audiences, local (mean r = +0.82) and foreign (mean r = +0.75). This relationship is specific to pride and does not generalize to other positive emotions that coactivate with pride but lack its audience-recalibrating function.

Predictors for recovery of macular function after surgery for primary macula-off rhegmatogenous retinal detachment.

PURPOSE: To determine predictors of best-corrected postoperative visual acuity (VA) in patients who underwent surgical intervention for macula-off rhegmatogenous retinal detachment. MATERIALS AND METHODS: Primary macula-off retinal detachments from the University of Colorado Primary Rhegmatogenous Retinal Detachment Database (2012-2017) were reviewed. The primary outcome measure was a postoperative VA of 20/40 or better at least 6 months after surgery. Patient demographics, medical history, duration of central vision loss before surgery, examination findings, operative technique, and postoperative findings were analyzed as possible predictors of postoperative visual recovery to 20/40 or better. Chi-square or Fisher's exact test was used to compare categorical variables, and Wilcoxon rank sum test was used for continuous variables. A multivariable logistic regression analysis was used to determine the adjusted odds ratios and 95% confidence intervals for variables that were significant in the univariable analyses. Statistical significance was set at p < 0.05. RESULTS: One hundred thirty-one patients met inclusion criteria. Eighty-one (61.8%) patients achieved a postoperative VA of 20/40 or better 6 or more months after surgery. Patients with a single retinal break were more likely than patients with more than one break to reach a postoperative VA of 20/40 or better (76.9% vs. 55.4%, p = 0.021). Patients with a better preoperative logMAR VA had better postoperative VA (p = 0.021). Duration of central vision loss prior to surgical repair was not related to final postoperative VA in this particular study. CONCLUSION: Postoperative recovery of visual acuity to 20/40 or better was significantly more common in patients with a single retinal break as well as in patients with better preoperative visual acuity. Duration of central vision loss prior to surgical repair was not significantly associated with postoperative VA.

Exchange Capability of Cationic Silver 4,4'-Bipyrdine Materials for Potential Water Remediation: Structure, Stability, and Anion Exchange Properties.

An in-depth study of the class of cationic materials [Ag(4,4'-bipy)+][X-] (where X- = CH3CO2-, NO3-, BF4-, ClO4-, and MnO4-) has led to key insights on the relationship between anion hydration energy, material structure, solubility, and stability. Since these materials show promise for their potential as water remediation tools, understanding their properties in detail is of significant importance. The structure of the starting and ending materials is the main driving force behind the resultant stability and solubility and can be successfully used to predict the ion exchange capabilities. The solubility trend was determined to be, from most soluble to least soluble, X- = CH3CO2- > NO3- ∼ BF4- > ClO4- > MnO4-. Kinetics and thermal stability also follow predictable trends but involve additional factors. For instance, the kinetics of NO3- to MnO4- exchange was much slower than expected based on that seen for NO3- to ClO4-. Powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the materials. Solubility was determined by inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis. Ion exchange was analyzed with ion chromatography (IC) and ultraviolet-visible spectroscopy (UV-vis), and thermal stability was determined with thermogravimetric analysis (TGA).

A Cationic Silver Pyrazine Coordination Polymer with High Capacity Anion Uptake from Water.

We report the first example of linker modification for an N-donor Ag-based cationic material while maintaining and in some cases increasing the anion exchange capacity. Cationic silver(I) pyrazine nitrate selectively traps harmful oxo-anions from water such as permanganate, perrhenate and a variety of α,ω-alkanedicarboxylates. We chose these anions as initial examples of exchange for potential water purification. The host-guest interaction between the cationic layers of π-stacked silver pyrazine polymers and the incoming/outgoing interlamellar anions allows for the exchange. The exchange capacity over 24 h reached 435 and 818 mg/g for permanganate and perrhenate, respectively, a record for a crystalline metal-organic material and over five times the exchange capacity compared to commercial resin. The material also undergoes organic exchange as an analog for pharmaceutical waste, some of which have a carboxylate functionality at the neutral pH range typical of natural water sources. Both the as-synthesized and exchanged materials are characterized by a variety of analytical techniques.

COLORADO AGE-RELATED MACULAR DEGENERATION REGISTRY: Design and Clinical Risk Factors of the Cohort.

PURPOSE: To study new and existing risk factors related to age-related macular degeneration (AMD) phenotypes in a Colorado cohort. METHODS: Age-related macular degeneration was categorized into early, intermediate, or advanced forms. Controls (n = 180) were patients with cataract and no AMD. Demographic and clinical data were gathered by patient interview and verified by chart review. Image data were reviewed by vitreoretinal specialists. Statistical analysis included univariable and multivariate logistic regression analysis (P < 0.05). RESULTS: Among the 456 patients with AMD, 157 (34.4%), 80 (17.6%), and 219 (48.0%) had the early/intermediate, geographic atrophy, and neovascular forms of the disease, respectively. Adjusted for age, African-American race was associated with a reduced risk of early/intermediate (adjusted odds ratio [AOR] = 0.08, confidence interval [CI] = 0.01-0.67) and neovascular AMD (AOR = 0.15, CI = 0.03-0.72). A family history of AMD was a risk factor for early/intermediate (AOR = 4.08, CI = 2.30-7.25), geographic atrophy (AOR = 8.62, CI = 3.77-19.7), and neovascular AMD (AOR = 3.76, CI = 2.16-6.56). A history of asthma was related to the early/intermediate form of AMD (AOR = 2.34, CI = 1.22-4.46). CONCLUSION: Studying AMD in specific populations may reveal novel risk factors such as our finding of a relationship between asthma history and AMD.

Reversible, Selective Trapping of Perchlorate from Water in Record Capacity by a Cationic Metal-Organic Framework.

We report the capture of ppm-level aqueous perchlorate in record capacity and kinetics via the complete anion exchange of a cationic metal-organic framework. Ambient conditions were used for both the synthesis of silver 4,4'-bipyridine nitrate (SBN) and the exchange, forming silver 4,4'-bipyridine perchlorate (SBP). The exchange was complete within 90 min, and the capacity was 354 mg/g, representing 99% removal. These values are greater than current anion exchangers such as the resins Amberlite IRA-400 (249 mg/g), Purolite A530E (104 mg/g), and layered double hydroxides (28 mg/g). Moreover, unlike resins and layered double hydroxides, SBN is fully reusable and displays 96% regeneration to SBN in nitrate solution, with new crystal formation allowing the indefinite cycling for perchlorate. We show seven cycles as proof of concept. Perchlorate contamination of water represents a serious health threat because it is a thyroid endocrine disruptor. This noncomplexing anionic pollutant is significantly mobile and environmentally persistent. Removal of other anionic pollutants from water such as chromate, pertechnetate, or arsenate may be possible by this methodology.

Progression of gyrate atrophy measured with ultra-wide-field imaging.

The study aims to determine the progression of gyrate atrophy by measuring the area growth of chorioretinal atrophic lesions using ultra-wide-field images (UWFI). A retrospective, observational, and comparative study was conducted and UWFI (200°) were obtained from two patients with gyrate atrophy at baseline and follow-up. Measurements of atrophy were obtained for three types of lesions: Solitary atrophic lesions (SAL), De novo solitary lesions (DNSL), and peripapillary atrophy (PPA). Comparison of baseline and follow-up was done using t tests. Two patients with gyrate atrophy were included. Patient 1 presented 16 SAL, 5 DNSL, and PPA measured for both eyes (BE). Overall area growth (OAG) for SAL (expressed in decimals) presented a mean of 3.41, σ 3.07. DNSL area for BE presented a mean of 1586.08 P (2), σ 1069.55. OAG for PPA presented a mean of 1.21, σ 0.17. Patient 2 presented 5 SAL, no DNSL, and PPA was measured for BE. OAG for SAL presented a mean of 1.58, σ 1.05 (range 1.02-3.47). OAG for PPA presented a mean of 1.05, σ 0.001. Gyrate atrophy progression can be determined by measuring the changes in area using UWFI.

Ocular disease in the cobalamin C defect: a review of the literature and a suggested framework for clinical surveillance.

The association between combined methylmalonic acidemia and homocystinuria of cblC type (cobalamin C defect, cblC) and ocular disease is now well recognized, and is a significant component of morbidity and disability associated with the condition. In this review, through collation of historically reported cases of early- and late-onset cblC and previously unreported cases, we have attempted to characterize the epidemiology, clinical features, and pathomechanisms of individual ocular features of cblC. These data suggest that maculopathy and nystagmus with abnormal vision are extremely common and affect the majority of children with early-onset cblC, usually before school age; strabismus and optic atrophy are also seen at relatively high frequency. The timing of progression of macular disease may coincide with a critical period of postnatal foveal development. Maculopathy and retinal disease may be subclinical and show only partial correlation with the extent of visual deficits, and visual deterioration may be relentlessly progressive in spite of aggressive treatment of biochemical abnormalities. In later-onset forms of the disease, visual loss and ocular complications appear to be infrequent. Finally, we discuss investigational strategies in diagnosing and characterizing eye disease in individuals with cblC, explore possible therapeutic avenues that may attenuate progression and severity of eye disease, and propose a clinical surveillance guideline for monitoring progression of ocular disease in children and adults with cblC.

Erbium hydroxide ethanedisulfonate: a cationic layered material with organic anion exchange capability.

We describe a cationic erbium-based material [Er12(OH)29(H2O)5][O3SCH2CH2SO3]3.5·5H2O. As synthesized, the material is water stable and capable of complete organic anion exchange for a variety of α,ω-alkanedicarboxylates. We chose these anions as initial examples of exchange and as an analog for pharmaceutical waste, some of which have a carboxylate functionality at neutral pH range. Free-floating and partially anchored organosulfonate anions reside between the cationic corrugated layers and allow for exchange. The structure also displays a reversible hydration event above 100 °C. Both the as-synthesized and the exchanged materials are characterized by a variety of analytical techniques.

Identification and biometry of horizontal extraocular muscle tendons using optical coherence tomography.

PURPOSE: To purpose if this study was to determine whether the horizontal rectus muscle tendons (HRMTs) can be observed using anterior segment optical coherence tomography (AS-OCT) and to determine the repeatability of its measurements. Also, this study aimed to observe and measure the different external ocular structures at the level of the horizontal rectus muscle (HRM) insertion. METHODS: This was a retrospective, observational, descriptive and comparative study. Images were obtained utilizing the RTVue 100 CAM system. Eyes were analyzed at the three and nine o'clock position. Scans were performed for three different locations: the limbus, the ciliary body and the equator. All scans were analyzed by two graders, separately and blinded. Measurements were performed for: HRMT length; HRM thickness; conjunctival epithelium thickness; conjunctiva and Tenon's capsule thickness; scleral thickness; and external ocular thickness. RESULTS: Results were obtained from twenty eyes of ten volunteers. The conjunctival epithelium thickness was 52.33 µm, the total conjunctiva/Tenon's capsule thickness was 313.54 µm, the medial rectus (MR) thickness was 136.63 µm and the lateral rectus (LR) thickness was 181.65 µm. The MR tendon length was 1,426.88 µm, the LR tendon length was 1,433.65 µm, the scleral thickness was 489.91 µm and the total external ocular structure thickness was 785.17 µm. Intra-observer reproducibility (intraclass correlation coefficient [ICC]) for tendon length was 0.993 for grader #1, 0.989 for grader #2; the muscle thickness ICC was 0.990 for grader #1 and 0.981 for grader #2. The inter-observer reproducibility ICC for tendon length was 0.557; the ICC for muscle thickness was 0.834. CONCLUSIONS: It is possible to visualize and measure HRMTs using AS-OCT. Measurements of the HRM, as well as the surrounding external ocular tissues, can be achieved.

Spectral domain optical coherence tomographic analysis of healthy retina in branch retinal vein occlusion and its response to antiangiogenic therapy.

PURPOSE: To propose a model that measures the effect of intravitreal bevacizumab (IVB) on relatively healthy retina. The purpose is to analyze the remote effect of a branch retinal vein occlusion in the healthy retina, to determine the response it may have to IVB, and to determine if IVB has an atrophic effect on the healthy retina. METHODS: Retrospective, longitudinal comparative analysis of patients with branch retinal vein occlusion treated with IVB. Eyes were divided into experimental (branch retinal vein occlusion eye) and control (contralateral eye) groups. Each eye was analyzed for thickness and area. Thickness measurements were performed for total retinal thickness, inner retina thickness, and outer retina thickness. Area was measured for photoreceptors, choroid, and total retina. RESULTS: Eighteen eyes of 9 patients. For thickness analysis, 1,050 scans were studied, and 126 measurements were performed on 42 scans for area analysis. No difference was observed for thickness, except for inner retina thickness. No difference was observed for area. No difference was observed when analyzing a cumulative exposure to IVB. CONCLUSION: There is no evidence to suggest an atrophic effect caused by IVB when analyzing thickness or area in this experiment. This model could be used to analyze the long-term safety of IVB in larger studies.

Teaching percutaneous renal biopsy using unfixed human cadavers.

BACKGROUND: Percutaneous renal biopsy (PRB) is an important diagnostic procedure. Despite advances in its safety profile there remains a small but significant risk of bleeding complications. Traditionally, operators train to perform PRB through tutor instruction and directly supervised PRB attempts on real patients. We describe an approach to teaching operators to perform PRB using cadaveric simulation. METHODS: We devised a full day course hosted in the Clinical Anatomy Skills Centre, with places for nine candidates. Course faculty consisted of two Consultant Nephrologists, two Nephrology trainees experienced in PRB, and one Radiologist. Classroom instruction included discussion of PRB indications, risk minimisation, and management of complications. Two faculty members acted as models for the demonstration of kidney localisation using real-time ultrasound scanning. PRB was demonstrated using a cadaveric model, and candidates then practised PRB using each cadaver model. RESULTS: Written candidate feedback was universally positive. Faculty considered the cadaveric model a realistic representation of live patients, while the use of multiple cadavers introduced anatomical variation. CONCLUSIONS: Our model facilitates safe simulation of a high risk procedure. This might reduce serious harm associated with PRB and improve patient safety, benefiting trainee operators and patients alike.

Current knowledge and trends in age-related macular degeneration: genetics, epidemiology, and prevention.

PURPOSE: To address the most dynamic and current issues concerning human genetics, risk factors, pharmacoeconomics, and prevention regarding age-related macular degeneration. METHODS: An online review of the database Pubmed and Ovid was performed, searching for the key words: age-related macular degeneration, AMD, pharmacoeconomics, risk factors, VEGF, prevention, genetics and their compound phrases. The search was limited to articles published since 1985 to date. All returned articles were carefully screened and their references were manually reviewed for additional relevant data. The webpage www.clinicaltrials.gov was also accessed in search of relevant research trials. RESULTS: A total of 366 articles were reviewed, including 64 additional articles extracted from the references and 25 webpages and online databases from different institutions. At the end, only 244 references were included in this review. CONCLUSION: Age-related macular degeneration is a complex multifactorial disease that has an uneven manifestation around the world but with one common denominator, it is increasing and spreading. The economic burden that this disease poses in developed nations will increase in the coming years. Effective preventive therapies need to be developed in the near future.

The hidden professionalism curriculum: Teach it, see it, do it and repeat!

Background: Professionalism is a complex and multifaceted component of medical education. Historically, students have learned about professionalism informally and as part of the hidden curriculum. Currently, professionalism is increasingly prominent in formal curricula, but uncertainty remains regarding optimal professionalism pedagogies. In this study, the authors explored medical students' exposure to professional topics and considered factors that enabled students to correctly recognize and manage these issues. Methods: Convenience sampling was used to recruit medical students from existing clinical attachments at the authors' hospital. A semi-structured interview format was used to explore participants' awareness of professional issues within fictional vignettes created using published regulatory guidance. The interview transcripts and interview guide field notes were then analyzed. Results: The data suggest that students require a combination of didactic teaching and experiential learning to reliably recognize and manage professional issues. Didactic teaching alone enabled topic recognition, but with uncertainty about management strategies. Experiential learning alone led to erratic recognition of the subject and reliance upon role modeling to guide its management. This work stimulates faculty development to enhance teaching professionalism. Conclusions: Undergraduate medical education on professionalism must be introduced into the formal curriculum. Didactic teaching is required to scaffold experiential learning. Failure to do so renders students unable to reliably recognize or manage professional issues encountered in clinical practice. Further research questions were identified to progress this work.

An evaluation of the West of Scotland in-programme Chief Resident role.

Background: Postgraduate leadership education is an evolving field. Locally we have an established 'Chief Residency' programme where centres have two to four senior trainees completing leadership duties alongside clinical workload, supported by local directors of medical education. This is twinned with a 4-day central training programme and peer-support network. Methods: To assess perspectives of the CR role, we adopted a qualitative case-study design using an electronic questionnaire delivered to previous chief residents between 2020 and 2023. Results were analysed using thematic analysis. Results: Trainees valued involvement within quality improvement and trainee support, demonstrating successful multi-departmental projects. Leadership education was viewed ubiquitously positively but participants felt further work is needed to address role legitimacy locally. A proposed solution was junior doctor leadership teams to address workload and emotional challenges. Conclusion: This model provides further evidence of the value in investing in trainee leadership positions, demonstrating organisational impact. Future work will research hospital peer leadership teams.