Constructing Diabatic States from Adiabatic States: Extending Generalized Mulliken–Hush to Multiple Charge Centers with Boys Localization

This article shows that, although Boys localization is usually applied to single-electron orbitals, the Boys method itself can be applied to many electron molecular states. For the two-state charge-transfer problem, we show analytically that Boys localization yields the same charge-localized diabatic states as those found by generalized Mulliken–Hush theory. We suggest that for future work in electron transfer, where systems have more than two charge centers, one may benefit by using a variant of Boys localization to construct diabatic potential energy surfaces and extract electronic coupling matrix elements. We discuss two chemical examples of Boys localization and propose a generalization of the Boys algorithm for creating diabatic states with localized spin density that should be useful for Dexter triplet-triplet energy transfer

The Initial and Final States of Electron and Energy Transfer Processes: Diabatization as Motivated by System-Solvent Interactions

For a system which undergoes electron or energy transfer in a polar solvent, we define the diabatic states to be the initial and final states of the system, before and after the nonequilibrium transfer process. We consider two models for the system-solvent interactions: A solvent which is linearly polarized in space and a solvent which responds linearly to the system. From these models, we derive two new schemes for obtaining diabatic states from ab initio calculations of the isolated system in the absence of solvent. These algorithms resemble standard approaches for orbital localization, namely, the Boys and Edmiston–Ruedenberg (ER) formalisms. We show that Boys localization is appropriate for describing electron transfer [ Subotnik et al., J. Chem. Phys. 129, 244101 (2008) ] while ER describes both electron and energy transfer. Neither the Boys nor the ER methods require definitions of donor or acceptor fragments and both are computationally inexpensive. We investigate one chemical example, the case of oligomethylphenyl-3, and we provide attachment/detachment plots whereby the ER diabatic states are seen to have localized electron-hole pairs

Mycobacterium tuberculosis Transmission between Cluster Members with Similar Fingerprint Patterns

Molecular epidemiologic studies provide evidence of transmission of Mycobacterium tuberculosis within clusters of patients whose isolates share identical IS6110-DNA fingerprint patterns. However, M. tuberculosis transmission among patients whose isolates have similar but not identical DNA fingerprint patterns (i.e., differing by a single band) has not been well documented. We used DNA fingerprinting, combined with conventional epidemiology, to show unsuspected patterns of tuberculosis transmission associated with three public bars in the same city. Among clustered TB cases, DNA fingerprinting analysis of isolates with similar and identical fingerprints helped us discover epidemiologic links missed during routine tuberculosis contact investigations

A Reconsideration of the Diagnosis and Management of Gastrointestinal Bleeding Based on its Epidemiology and Outcomes Analysis

Background: Traditionally, gastrointestinal bleeding (GIB) has been divided into upper and lower GIB with little consideration of the small bowel as a source. Furthermore, melena is generally included in the upper category, despite its poor localization value. We analyzed 341 consecutive GIB patients to see if those presenting with melena/hematocheiza have less efficient evaluations then when compared to those presenting with hematemesis. Methods: A retrospective analysis was performed for 341 consecutive patients admitted to our ED with GIB over a year. Cohorts were separated based on presenting symptom to the ED, hematemesis (G1) and non-hematemesis (G2). Data obtained included demographics, diagnosis, number and type of procedure, diagnostic yield of each procedure, hours to diagnosis, ICU days, and total hospital days. Results: G1 (n=105, 62%M) was younger than G2 (n=231, 53%M) with a mean age of 54 vs. 66, p≤0.001. 78% and 98% of patients were admitted to the hospital in G1 and G2 respectively (p=0.02). Median time to diagnosis was 14.0 hours and 20.0 hours for G1 and G2 respectively (p≤0.001). Median number of days in the ICU was 3.0 in both groups, and median number of hospital days was 3.0 for G1 vs. 4.0 for G2 (p=0.267). In G1, the 1st procedure was diagnostic 69% of the time vs 54% for G2 (p=0.07). The overall diagnostic yield for EGDs in G1 was 58% vs. 51% in G2 (p=0.279). Colonoscopies overall were diagnostic 39% of the time in G2 and, interestingly, VCEs were the most diagnostic, yielding a diagnosis 74% of the time in G2 (n= 34). Unexpectedly, those admitted in G1 had a confirmed diagnosis only 61% of the time compared to 62% in G2. Conclusion: Our data suggests that a portion of patients presenting with non-hematemesis (G2) are inefficiently managed and a search for an alternative strategy is warranted. Early deployment of VCE may be a more efficient and economic option, although prospective evaluation of this concept is needed

Reliability of the Coach’s Eye goniometer application during squat exercise

This study examined the test re-test, intrarater and interrater reliability of joint kinematics from the Coach’s Eye smartphone application. Twenty-two males completed a 1-repetition maximum (1-RM) assessment followed by 2 identical sessions using 5 incremental loads (20%-40%-60%-80%-90% 1-RM). Peak flexion angles at the hip, knee, and ankle joints were assessed using 1 experienced practitioner and 1 inexperienced practitioner. The acceptable reliability thresholds were defined as intraclass correlation coefficient (ICC) (r) > 0.70 and coefficient of variation (CV) ≤ 10%. The test re-test reliability of peak hip and knee flexion were reliable across 20-90% 1-RM (r > 0.64; CV 0.70; CV 0.11). The intrarater reliability was near perfect (r > 0.90) except for peak ankle flexion (r > 0.85). The interrater reliability was nearly perfect (r > 0.91) except for hip flexion at 80% 1-RM and ankle flexion at 20% (r > 0.77). Concludingly, the Coach’s Eye application can produce repeatable assessments of joint kinematics using either a single examiner or 2 examiners, regardless of experience level. The Coach’s Eye can accurately monitor squat depth

A Year of Gastrointestinal Bleeding: An Epidemiologic Study

Background: For decades the diagnosis and management of gastrointestinal bleeding (GIB) has been based largely on endoscopy. Studying a large cohort of patients presenting to the ED we may find cost-effective alternatives in the management of GIB. We analyzed the epidemiology and initial disposition of all patients who presented to our ED from the perspective of hematemesis versus non-hematemesis, to identify patterns among each cohort’s presentations to aid in this. Methods: Retrospective analysis of medical records for 338 patients presenting to the UMass ED. Two cohorts were identified: those with hematemesis (G1) or non-hematemesis (G2). Results: 105 patients presented to the ED with hematemesis (G1), 233 patients presented with non-hematemesis GIB (G2). G1 was younger than G2 (54.4 years vs. 65.6 years, p\u3c0.001). There were more males in G1 vs. G2 (61% vs. 53%, p=0.154). Comorbities in G1 were liver disease (21%), alcohol abuse (20%), and diabetes (11%). Comorbities in G2 were coronary artery disease (22%), atrial fibrillation (13.7%), and diverticulosis (8%). More patients in G2 than G1 used Coumadin (23% vs. 7%, p\u3c0.001), anti-platelet agents (12% and 3%, p\u3c0.004), and NSAIDs (40% and 32%y, p=0.203). Admission hematocrit was greater in G1 compared to G2 (34.1 vs. 30.0, p\u3c0.001). INR was greater in G2 compared to G1 (1.7 vs. 1.3, p=0.03). BUN was greater in G2 compared to G1 (30.2 vs. 23.6, p=0.021). More patients in G2 were admitted compared to G1 (89.6% vs. 78.1%, p=0.019). More were admitted to the ICU in G1 compared to G2 (46% vs. 38%, p=0.237).Discussion: This study uses a novel approach that elicits different patterns than the traditional delineation of upper versus lower GIB. These results may lead to new decision-making in patients presenting with GIB, allowing for new diagnostic and management paradigms, resulting in cost-effective care

Skeletal Deficits in Male and Female down Syndrome Model Mice Arise Independent of Normalized Dyrk1a Expression in Osteoblasts

Trisomy 21 (Ts21) causes alterations in skeletal development resulting in decreased bone mass, shortened stature and weaker bones in individuals with Down syndrome (DS). There is a sexual dimorphism in bone mineral density (BMD) deficits associated with DS with males displaying earlier deficits than females. The relationships between causative trisomic genes, cellular mechanisms, and influence of sex in DS skeletal abnormalities remain unknown. One hypothesis is that the low bone turnover phenotype observed in DS results from attenuated osteoblast function, contributing to impaired trabecular architecture, altered cortical geometry, and decreased mineralization. DYRK1A, found in three copies in humans with DS, Ts65Dn, and Dp1Tyb DS model mice, has been implicated in the development of postnatal skeletal phenotypes associated with DS. Reduced copy number of Dyrk1a to euploid levels from conception in an otherwise trisomic Ts65Dn mice resulted in a rescue of appendicular bone deficits, suggesting DYRK1A contributes to skeletal development and homeostasis. We hypothesized that reduction of Dyrk1a copy number in trisomic osteoblasts would improve cellular function and resultant skeletal structural anomalies in trisomic mice. Female mice with a floxed Dyrk1a gene (Ts65Dn,Dyrk1afl/wt) were mated with male Osx-Cre+ (expressed in osteoblasts beginning around E13.5) mice, resulting in reduced Dyrk1a copy number in mature osteoblasts in Ts65Dn,Dyrk1a+/+/Osx-Cre P42 male and female trisomic and euploid mice, compared with littermate controls. Male and female Ts65Dn,Dyrk1a+/+/+ (3 copies of DYRK1A in osteoblasts) and Ts65Dn,Dyrk1a+/+/Osx-Cre (2 copies of Dyrk1a in osteoblasts) displayed similar defects in both trabecular architecture and cortical geometry, with no improvements with reduced Dyrk1a in osteoblasts. This suggests that trisomic DYRK1A does not affect osteoblast function in a cell-autonomous manner at or before P42. Although male Dp1Tyb and Ts65Dn mice exhibit similar skeletal deficits at P42 in both trabecular and cortical bone compartments between euploid and trisomic mice, female Ts65Dn mice exhibit significant cortical and trabecular deficits at P42, in contrast to an absence of genotype effect in female Dp1Tyb mice in trabecular bone. Taken together, these data suggest skeletal deficits in DS mouse models and are sex and age dependent, and influenced by strain effects, but are not solely caused by the overexpression of Dyrk1a in osteoblasts. Identifying molecular and cellular mechanisms, disrupted by gene dosage imbalance, that are involved in the development of skeletal phenotypes associated with DS could help to design therapies to rescue skeletal deficiencies seen in DS

Enhanced viability of corneal epithelial cells for efficient transport/storage using a structurally-modified calcium alginate hydrogel

Aims: Therapeutic limbal epithelial stem cells could be managed more efficiently if clinically validated batches were transported for ‘on-demand’ use. Materials & methods: In this study, corneal epithelial cell viability in calcium alginate hydrogels was examined under cell culture, ambient and chilled conditions for up to 7 days. Results: Cell viability improved as gel internal pore size increased, and was further enhanced with modification of the gel from a mass to a thin disc. Ambient storage conditions were optimal for supporting cell viability in gel discs. Cell viability in gel discs was significantly enhanced with increases in pore size mediated by hydroxyethyl cellulose. Conclusion: Our novel methodology of controlling alginate gel shape and pore size together provides a more practical and economical alternative to established corneal tissue/cell storage methods

Reliability of the Coach’s Eye Goniometer Application during Squat Exercise

This study examined the test re-test, intrarater and interrater reliability of joint kinematics from the Coach’s Eye smartphone application. Twenty-two males completed a 1-repetition maximum (1-RM) assessment followed by 2 identical sessions using 5 incremental loads (20%-40%-60%-80%-90% 1-RM). Peak flexion angles at the hip, knee, and ankle joints were assessed using 1 experienced practitioner and 1 inexperienced practitioner. The acceptable reliability thresholds were defined as intraclass correlation coefficient (ICC) (r) > 0.70 and coefficient of variation (CV) ≤ 10%. The test re-test reliability of peak hip and knee flexion were reliable across 20-90% 1-RM (r > 0.64; CV 0.70; CV 0.11). The intrarater reliability was near perfect (r > 0.90) except for peak ankle flexion (r > 0.85). The interrater reliability was nearly perfect (r > 0.91) except for hip flexion at 80% 1-RM and ankle flexion at 20% (r > 0.77). Concludingly, the Coach’s Eye application can produce repeatable assessments of joint kinematics using either a single examiner or 2 examiners, regardless of experience level. The Coach’s Eye can accurately monitor squat depth

Transmission of Mycobacterium tuberculosis in a Rural Community, Arkansas, 1945–2000

A cluster of tuberculosis cases in a rural community in Arkansas persisted from 1991 to 1999. The cluster had 13 members, 11 linked epidemiologically. Old records identified 24 additional patients for 40 linked case-patients during a 54-year period. Residents of this neighborhood represent a population at high risk who should be considered for tuberculin testing and treatment for latent tuberculosis infection