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1.
Prev Med ; 99: 29-36, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28189810

RESUMO

During vacations, many individuals receive high-risk sun exposure that is associated with skin cancer. Vacationers in outdoor recreation venues (pretest n=4347; posttest n=3986) at warm-weather destination resorts in North America (n=41) were enrolled in a pair-matched, group-randomized pretest-posttest controlled quasi-experimental design in 2012-14. Print, audiovisual, and online messages based on Transportation Theory and Diffusion of Innovation Theory and promoting advanced sun protection (e.g., use of clothing, hats, shade and pre-application/reapplication of sunscreen and reliable cues to high UV) were delivered through resort channels. Vacationers' sun protection practices observed by trained research staff (i.e., body coverage and shade use analyzed individually and in combined scores) did not differ by experimental condition (p>0.05) or intervention implementation (p>0.05). However, recreation venue moderated intervention impact. The intervention improved sun protection at waterside recreation venues (z-score composite: intervention pre=-22.74, post=-15.77; control pre=-27.24, post=-23.24) but not non-waterside venues (z-score composite: intervention pre=20.43, post=20.53; control pre=22.94, post=18.03, p<0.01). An additional analysis showed that resorts with greater program implementation showed more improvements in sun protection by vacationers at waterside (z=score composite: high implementation pre=-25.45, post=-14.05; low implementation pre=-24.70, post=-21.40) compared to non-waterside (z-score composite: high implementation pre=14.51, post=19.98; low implementation pre=24.03, post=18.98, p<0.01) recreation venues. The intervention appeared effective with the vacationers in recreation venues with the highest-risk for sun exposure, waterside venues. However, it was not effective throughout all the resort venues, possibly because of the sun-seeking desires of vacationers, information overload at the resorts, and constraints on clothing styles and sun protection by recreation activity.


Assuntos
Promoção da Saúde/métodos , Recreação , Neoplasias Cutâneas/prevenção & controle , Protetores Solares/uso terapêutico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte , Roupa de Proteção/estatística & dados numéricos , Queimadura Solar/prevenção & controle , Raios Ultravioleta/efeitos adversos
2.
J Health Commun ; 22(12): 951-963, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29161214

RESUMO

Taking vacations in sunny locations is associated with the development of skin cancer. This study tested a multi-component sun protection intervention based on diffusion of innovations theory and transportation theory designed to increase vacationers' comprehensive sun protection, i.e., use of clothing, hats, and shade, and use, pre-application, and reapplication of sunscreen. The trial enrolled 41 warm weather resorts in North America in a pair-matched group randomized pretest-posttest design and assessed samples of adult vacationers at resort outdoor recreation venues regarding sun protection at pretest (n = 3,531) and posttest (n = 3,226). While results showed no overall effect of the intervention on comprehensive sun protection across venues, the intervention produced statistically significant improvements in sun protection at waterside venues (pools and beaches). The intervention's overall effects may have been impeded by a lack of uniformly robust implementation, low interest in skin cancer prevention by guests, or shortcomings of the theories used to create prevention messages. The intervention may have worked best with guests in the highest-risk recreation venue, i.e., waterside recreation where they exposed the most skin. Alternative approaches that alter resort organizations, such as through changes in policy, environmental features, or occupational efforts might be more effective than targeting vacationers with behavior-change messages.


Assuntos
Promoção da Saúde/métodos , Roupa de Proteção/estatística & dados numéricos , Recreação , Neoplasias Cutâneas/prevenção & controle , Protetores Solares/uso terapêutico , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte , Avaliação de Programas e Projetos de Saúde , Queimadura Solar/prevenção & controle , Raios Ultravioleta/efeitos adversos , Adulto Jovem
3.
Environ Res ; 146: 200-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26775001

RESUMO

BACKGROUND: Vacationing at sunny, warm weather locations is a risk factor for excessive solar ultraviolet (UV) radiation exposure and skin cancer. OBJECTIVES: This study examined the association of environmental variables related to UV levels with vacationers' sun protection. METHODS: Vacationers at 41 summer resorts in 17 states and 1 Canadian Province were interviewed (n=3531) and observed (N=4347) during 2012 and 2013. Clothing coverage, sunglasses, and shade use were observed. Use of sunscreen and sunburns were self-reported. Environmental information was recorded by research staff or acquired from ground stations and the weather service. RESULTS: Temperature was positively associated with sun protection behaviors; however clothing coverage was negatively associated with temperature. Cloud cover was negatively associated with sun protection, with the exception of clothing coverage which was positively associated with it. Elevation showed a mixed pattern of associations with vacationer's sun protection. Latitude of a resort was negatively associated with most sun protection behaviors, such that sun protection increased at more southerly resorts. Similarly, the farther south a vacationer traveled to the resort, the less sun protection they employed. The UV index showed a weak, positive relationship with some sun protection behaviors even when controlling for temperature. CONCLUSIONS: Vacationers appeared aware that UV is higher at southern latitudes and may learn UV is intense when living in southern regions. However, many used temperature, an unreliable cue, to judge UV intensity and seemed to adjust clothing for warmth not UV protection. Efforts are needed to help individuals make more accurate sun safety decisions.


Assuntos
Exposição Ambiental/prevenção & controle , Queimadura Solar/prevenção & controle , Protetores Solares/administração & dosagem , Raios Ultravioleta/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Altitude , Canadá , Vestuário , Feminino , Geografia , Humanos , Masculino , Pessoa de Meia-Idade , Estações do Ano , Luz Solar/efeitos adversos , Temperatura , Estados Unidos , Tempo (Meteorologia) , Adulto Jovem
4.
Kans J Med ; 15: 170-174, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646258

RESUMO

Introduction: Anemia is a common medical disorder seen in consultation by hematologists. This study was performed to determine the incidence of the etiologies causing anemia in patients referred to the hematologists at Tammy Walker Cancer Center (TWCC) in the rural Kansas community of Salina. An additional goal of the study was to compare the frequencies of different etiologies for anemia in this cohort of patients with those previously reported by four academic medical centers. Methods: A retrospective review of the medical records of 152 patients seen at TWCC between August 2015 and May 2019 was performed. The patient's history and physical exam, complete blood count, and various additional hematologic studies ordered at the discretion of the TWCC hematologist were used to determine the etiology of each patient's anemia. Results: The most common causes of anemia found in the chart review were iron deficiency (48.7%), hematologic malignancy (14.5%), chronic inflammation (13.8%), renal insufficiency (11.2%), and unexplained anemia (9.9%). While the incidences of anemia due to hematologic malignancy, chronic inflammation, and renal insufficiency were like that reported previously by four academic medical centers, significantly more iron deficiency and less unexplained anemia were found in the patients referred to TWCC. Conclusions: The causes of anemia in patients seen at TWCC were similar to those reported by academic medical centers; however, the incidences were different. The differences in findings may reflect dissimilarities in the demographics of referral populations, the duration, and extent of the evaluation at TWCC, or referral patterns.

5.
NPJ Breast Cancer ; 8(1): 80, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35817765

RESUMO

Triple-negative breast cancer (TNBC) is classically defined by estrogen receptor (ER) and progesterone receptor (PR) immunohistochemistry expression <1% and absence of HER2 amplification/overexpression. HER2-negative breast cancer with low ER/PR expression (1-10%) has a gene expression profile similar to TNBC; however, real-world treatment patterns, chemotherapy response, endocrine therapy benefit, and survival outcomes for the Low-ER group are not well known. 516 patients with stage I-III HER2-negative breast cancer and ER/PR expression ≤10% who were enrolled in a multisite prospective registry between 2011 and 2019 were categorized on the basis of ER/PR expression. TNBC (ER and PR < 1%) and Low-ER (ER and/or PR 1-10%) groups comprised 87.4% (n = 451) and 12.6% (n = 65) of patients, respectively. Demographic, clinical, and treatment characteristics, including prevalence of germline BRCA1/2 mutation, racial and ethnic distribution, and chemotherapy use were not different between TNBC and Low-ER groups. No difference was observed in recurrence-free survival (RFS) and overall survival (OS) between TNBC and Low-ER groups (3-year RFS 82.5% versus 82.4%, respectively, p = 0.728; 3-year OS 88.0% versus 83.4%, respectively, p = 0.632). Among 358 patients receiving neoadjuvant chemotherapy, rates of pathologic complete response were similar for TNBC and Low-ER groups (49.2% vs 51.3%, respectively, p = 0.808). The HER2-negative Low-ER group is often excluded from TNBC clinical trials assessing novel treatments (immunotherapy and antibody-drug conjugates), thus limiting efficacy data for newer effective therapies in this group. Given that HER2-negative Low-ER disease displays clinical characteristics and outcomes similar to TNBC, inclusion of this group in TNBC clinical trials is encouraged.

6.
Clin Cancer Res ; 27(4): 975-982, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33208340

RESUMO

PURPOSE: Addition of carboplatin (Cb) to anthracycline chemotherapy improves pathologic complete response (pCR), and carboplatin plus taxane regimens also yield encouraging pCR rates in triple-negative breast cancer (TNBC). Aim of the NeoSTOP multisite randomized phase II trial was to assess efficacy of anthracycline-free and anthracycline-containing neoadjuvant carboplatin regimens. PATIENTS AND METHODS: Patients aged ≥18 years with stage I-III TNBC were randomized (1:1) to receive either paclitaxel (P) weekly × 12 plus carboplatin AUC6 every 21 days × 4 followed by doxorubicin/cyclophosphamide (AC) every 14 days × 4 (CbP → AC, arm A), or carboplatin AUC6 + docetaxel (D) every 21 days × 6 (CbD, arm B). Stromal tumor-infiltrating lymphocytes (sTIL) were assessed. Primary endpoint was pCR in breast and axilla. Other endpoints included residual cancer burden (RCB), toxicity, cost, and event-free (EFS) and overall survival (OS). RESULTS: One hundred patients were randomized; arm A (n = 48) or arm B (n = 52). pCR was 54% [95% confidence interval (CI), 40%-69%] in arm A and 54% (95% CI, 40%-68%) in arm B. RCB 0+I rate was 67% in both arms. Median sTIL density was numerically higher in those with pCR compared with those with residual disease (20% vs. 5%; P = 0.25). At median follow-up of 38 months, EFS and OS were similar in the two arms. Grade 3/4 adverse events were more common in arm A compared with arm B, with the most notable differences in neutropenia (60% vs. 8%; P < 0.001) and febrile neutropenia (19% vs. 0%; P < 0.001). There was one treatment-related death (arm A) due to acute leukemia. Mean treatment cost was lower for arm B compared with arm A (P = 0.02). CONCLUSIONS: The two-drug CbD regimen yielded pCR, RCB 0+I, and survival rates similar to the four-drug regimen of CbP → AC, but with a more favorable toxicity profile and lower treatment-associated cost.


Assuntos
Antraciclinas/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carboplatina/administração & dosagem , Terapia Neoadjuvante/métodos , Neoplasias de Mama Triplo Negativas/terapia , Adulto , Idoso , Antraciclinas/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/efeitos adversos , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Estadiamento de Neoplasias , Neoplasia Residual , Intervalo Livre de Progressão , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia
7.
Am J Health Educ ; 48(2): 90-99, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29147456

RESUMO

BACKGROUND: Exposure to solar ultra violet radiation (UVR) is a primary risk factor for skin cancer. Vacationers often fail to protect themselves from harmful UVR. PURPOSE: The study assessed the sun protection practices of resort guests in various outdoor leisure and recreation venues during warm-weather seasons. METHOD: 41 North American resorts were enrolled in a quasi-experimental randomized controlled trial. Adult guests were observed (n=4091) and surveyed (n=3694) in a cross sectional sample. Data collection was conducted in recreation and leisure venues with outdoors commons/reception areas acting as the comparison condition. RESULTS: The mean percent of vacationers at pools and beaches were more likely (p < 0.001) to wear sunscreen than in commons areas but less likely (p < 0.001) to wear cover-up clothing or use shade. In both samples, the combined sun protection scores were higher in commons areas compared to all venues except for outdoor dining (p < 0.001). DISCUSSION: Sun safety was suboptimal in all venues and was potentially mitigated by venue type. TRANSLATION TO HEALTH EDUCATION PRACTICE: Approaches are needed to encourage vacationers to practice comprehensive sun protection and to work with resorts to construct built environments that facilitate rather than act as barriers to sun safety.

9.
Contemp Clin Trials ; 46: 67-76, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26593781

RESUMO

INTRODUCTION: Exposure to solar ultraviolet radiation during recreation is a risk factor for skin cancer. A trial evaluated an intervention to promote advanced sun protection (sunscreen pre-application/reapplication; protective hats and clothing; use of shade) during vacations. MATERIALS AND METHODS: Adult visitors to hotels/resorts with outdoor recreation (i.e., vacationers) participated in a group-randomized pretest-posttest controlled quasi-experimental design in 2012-14. Hotels/resorts were pair-matched and randomly assigned to the intervention or untreated control group. Sun. protection (e.g., clothing, hats, shade and sunscreen) was measured in cross-sectional samples by observation and a face-to-face intercept survey during two-day visits. RESULTS: Initially, 41 hotel/resorts (11%) participated but 4 dropped out before posttest. Hotel/resorts were diverse (employees=30 to 900; latitude=24° 78' N to 50° 52' N; elevation=2ft. to 9726ft. above sea level), and had a variety of outdoor venues (beaches/pools, court/lawn games, golf courses, common areas, and chairlifts). At pretest, 4347 vacationers were observed and 3531 surveyed. More females were surveyed (61%) than observed (50%). Vacationers were mostly 35-60years old, highly educated (college education=68%) and non-Hispanic white (93%), with high-risk skin types (22%). Vacationers reported covering 60% of their skin with clothing. Also, 40% of vacationers used shade; 60% applied sunscreen; and 42% had been sunburned. CONCLUSIONS: The trial faced challenges recruiting resorts but result showed that the large, multi-state sample of vacationers were at high risk for solar UV exposure.


Assuntos
Comportamentos Relacionados com a Saúde , Promoção da Saúde/métodos , Férias e Feriados , Roupa de Proteção , Recreação , Neoplasias Cutâneas/prevenção & controle , Protetores Solares/uso terapêutico , Adulto , Estudos Transversais , Feminino , Estâncias para Tratamento de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
10.
J Bone Miner Res ; 20(4): 625-34, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15765182

RESUMO

UNLABELLED: NMR was used to study the nanostructure of bone tissue. Distance measurements show that the first water layer at the surface of the mineral in cortical bone is structured. This water may serve to couple the mineral to the organic matrix and may play a role in deformation. INTRODUCTION: The unique mechanical characteristics of bone tissue have not yet been satisfactorily connected to the exact molecular architecture of this complex composite material. Recently developed solid-state nuclear magnetic resonance (NMR) techniques are applied here to the mineral component to provide new structural distance constraints at the subnanometer scale. MATERIALS AND METHODS: NMR dipolar couplings between structural protons (OH(-) and H(2)O) and phosphorus (PO(4)) or carbon (CO(3)) were measured using the 2D Lee-Goldburg Cross-Polarization under Magic-Angle Spinning (2D LG-CPMAS) pulse sequence, which simultaneously suppresses the much stronger proton-proton dipolar interactions. The NMR dipolar couplings measured provide accurate distances between atoms, e.g., OH and PO(4) in apatites. Excised and powdered femoral cortical bone was used for these experiments. Synthetic carbonate ( approximately 2-4 wt%)-substituted hydroxyapatite was also studied for structural comparison. RESULTS: In synthetic apatite, the hydroxide ions are strongly hydrogen bonded to adjacent carbonate or phosphate ions, with hydrogen bond (O-H) distances of approximately 1.96 A observed. The bone tissue sample, in contrast, shows little evidence of ordered hydroxide. Instead, a very ordered (structural) layer of water molecules is identified, which hydrates the small bioapatite crystallites through very close arrangements. Water protons are approximately 2.3-2.55 A from surface phosphorus atoms. CONCLUSIONS: In synthetic carbonated apatite, strong hydrogen bonds were observed between the hydroxide ions and structural phosphate and carbonate units in the apatite crystal lattice. These hydrogen bonding interactions may contribute to the long-range stability of this mineral structure. The biological apatite in cortical bone tissue shows evidence of hydrogen bonding with an ordered surface water layer at the faces of the mineral particles. This structural water layer has been inferred, but direct spectroscopic evidence of this interstitial water is given here. An ordered structural water layer sandwiched between the mineral and the organic collagen fibers may affect the biomechanical properties of this complex composite material.


Assuntos
Osso e Ossos/química , Água/química , Animais , Apatitas/química , Densidade Óssea , Bovinos , Fêmur/química , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Nanoestruturas/química
11.
Environ Sci Technol ; 40(8): 2572-7, 2006 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-16683594

RESUMO

The dissociation of hexafluorosilicate has been reinvestigated due to recent suggestions that fluorosilicate intermediates may be present in appreciable concentrations in drinking water. 19F NMR spectroscopy has been used to search for intermediates in the hydrolysis of hexafluorosilicate. No intermediates were observable at 10(-5) M concentrations under excess fluoride forcing conditions over the pH range of 3.5-5. A single intermediate species, assigned as SiF5(-) or its hydrate, was detected below pH 3.5. At moderate pH values of 4 and 5 silica oligomerization in the solutions studied made it difficult to directly determine the hexafluorosilicate equilibrium constant. Under more acidic conditions the average pKd, or negative log of the dissociation constant Kd, determined by 19F NMR measurements, was 30.6. We also investigated the behavior of hexafluorosilicate in common biological buffer reagents including phosphate/citrate, veronal/HCI buffers, and Ringer's solution. The buffer capacity of all of these systems was found to be insufficient to prevent acidic shifts in pH when hexafluorosilicate was added. The pH change is sufficient explanation for the observed inhibition of acetylcholinesterase that was previously attributed to hexafluorosilicate hydrolysis intermediates.


Assuntos
Fluoretação , Fluoretos/química , Ácido Silícico/química , Barbital/química , Soluções Tampão , Ácido Cítrico/química , Ácido Clorídrico/química , Concentração de Íons de Hidrogênio , Hidrólise , Soluções Isotônicas/química , Isótopos , Espectroscopia de Ressonância Magnética , Fosfatos/química , Solução de Ringer , Poluentes Químicos da Água
12.
Biophys J ; 90(10): 3722-31, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16500963

RESUMO

Hydrogen-bearing species in the bone mineral environment were investigated using solid-state NMR spectroscopy of powdered bone, deproteinated bone, and B-type carbonated apatite. Using magic-angle spinning and cross-polarization techniques three types of structurally-bound water were observed in these materials. Two of these water types occupy vacancies within the apatitic mineral crystal in synthetic carbonated apatite and deproteinated bone and serve to stabilize these defect-containing crystals. The third water was observed at the mineral surface in unmodified bone but not in deproteinated bone, suggesting a role for this water in mediating mineral-organic matrix interactions. Direct evidence of monohydrogen phosphate in a (1)H NMR spectrum of unmodified bone is presented for the first time. We obtained clear evidence for the presence of hydroxide ion in deproteinated bone by (1)H MAS NMR. A (1)H-(31)P heteronuclear correlation experiment provided unambiguous evidence for hydroxide ion in unmodified bone as well. Hydroxide ion in both unmodified and deproteinated bone mineral was found to participate in hydrogen bonding with neighboring water molecules and ions. In unmodified bone mineral hydroxide ion was found, through a (1)H-(31)P heteronuclear correlation experiment, to be confined to a small portion of the mineral crystal, probably the internal portion.


Assuntos
Água Corporal/química , Água Corporal/fisiologia , Calcificação Fisiológica/fisiologia , Fêmur/química , Fêmur/fisiologia , Espectroscopia de Ressonância Magnética/métodos , Animais , Bovinos , Técnicas In Vitro , Conformação Molecular , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie
13.
J Am Chem Soc ; 125(48): 14708-9, 2003 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-14640637

RESUMO

The Bergman cyclization has long been known to produce polymers as side products. More recently, this attribute has been harnessed for the production of conjugated materials. However, the structures of these polymers have not been established. To resolve this question, the metal-catalyzed polymerization of 1,4-dibromonaphthalene and thermal polymerization of o-diethynylbenzene were conducted. Two distinct polymers were obtained. Comparison of IR spectroscopy, MALDI-TOF MS, solid-state NMR spectroscopy, UV-vis reflectance spectroscopy, and pyrolysis GC-MS data indicates that only one of the polymers is consistent with poly(1,4-naphthalene).

14.
Inorg Chem ; 43(24): 7665-70, 2004 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-15554631

RESUMO

The combination of 2 equiv of bis[bis(trimethylsilyl)amide]germylene (5) with 2 equiv of 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) in tetrahydrofuran (THF) results in the ring-opening of 1 equiv of THF to form 2,2,8,8-tetrakis(1,1,1,3,3,3-hexamethyl-disilazan-2-yl)-5,16-diphenyl-7,9,14-trioxa-1,3,5,16,18,19-hexaaza-2,8-digerma-tricyclo[13.2.1.13,6]nonadeca-6(19),15(18)-diene-4,17-dione (6). This fast and nearly quantitative reaction builds a 15-membered ring from five different molecules. The new ring, structurally assigned by X-ray crystallography, contains a flexible methylene chain that moves rapidly on the NMR time scale.

15.
J Am Chem Soc ; 124(24): 7024-34, 2002 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-12059226

RESUMO

A set of zeolite synthesis experiments is described where lattice substitution is varied in the context of the structure of particular structure-directing organocations (at times referred to as templates). In this particular series, the organocations are constructed as members of a fused bicyclo organonitrogen class of compounds, described as having ring construction [l.m.n], where n = 0. We show that these compounds can best be achieved from starting cyclic ketones that are converted to imines via a Beckman rearrangement reaction. A particular approach to the Beckmann reaction works best in our hands. In some instances isomeric organocations are made and separated. Often their use in zeolite synthesis led to different products. There is a high correlation for the space-filling details of the guest organocations and the type of crystalline host lattice developed in the synthesis. In one instance involving isomers of a decahydroquinoline derivative, a new zeolite, SSZ-48, is discovered and contains only one of the isomers. Characterization of the isomers and their use in the zeolites is followed by (13)C MAS NMR analyses. Some details of the new zeolite are given and it is shown that a reasonable symmetry operation predicting a 14-ring zeolite could be generated under similar conditions to SSZ-48 (a 12-ring zeolite).

16.
J Am Chem Soc ; 124(18): 4942-3, 2002 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-11982342

RESUMO

The reaction of pentaerythritol and tetraethylorthocarbonate at 260 degrees C for 12 h yields a white crystalline material that was characterized by 13C CPMAS NMR, CHN analysis, FT-IR, electron and X-ray powder diffraction, and Rietveld analysis. The white crystalline material was found to have the formula C6H8O4 and a crystal structure with a monoclinic cell [a = 9.167 A, b = 5.681 A, c = 5.880 A, beta = 90.0 degrees , space group I2] of hexagonally arranged spiro-oligomeric chains.

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