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1.
Proc Natl Acad Sci U S A ; 120(42): e2307520120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37816056

RESUMO

Isolation of the Caribbean Sea from the tropical Eastern Pacific by uplift of the Isthmus of Panama in the late Pliocene was associated with major, taxonomically variable, shifts in Caribbean biotic composition, and extinction, but inferred causes of these biological changes have remained elusive. We addressed this through falsifiable hypotheses about how independently determined historical changes in oceanographic conditions may have been responsible. The most striking environmental change was a sharp decline in upwelling intensity as measured from decreases in intra-annual fluctuations in temperature and consequently in planktonic productivity. We then hypothesized three general categories of biological response based upon observed differences in natural history between the oceans today. These include changes in feeding ecology, life histories, and habitats. As expected, suspension feeders and predators became rarer as upwelling declined. However, predicted increases in benthic productivity by reef corals, and benthic algae were drawn out over more than 1 Myr as seagrass and coral reef habitats proliferated; a shift that was itself driven by declining upwelling. Similar time lags occurred for predicted shifts in reproductive life history characteristics of bivalves, gastropods, and bryozoans. Examination of the spatial variability of biotic change helps to understand the time lags. Many older species characteristic of times before environmental conditions had changed tended to hang on in progressively smaller proportions of locations until they became extinct as expected from metapopulation theory and the concept of extinction debt. Faunal turnover may not occur until a million or more years after the environmental changes ultimately responsible.


Assuntos
Antozoários , Ecossistema , Animais , Região do Caribe , Ecologia , Recifes de Corais
2.
Nature ; 546(7656): 82-90, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28569801

RESUMO

Coral reefs support immense biodiversity and provide important ecosystem services to many millions of people. Yet reefs are degrading rapidly in response to numerous anthropogenic drivers. In the coming centuries, reefs will run the gauntlet of climate change, and rising temperatures will transform them into new configurations, unlike anything observed previously by humans. Returning reefs to past configurations is no longer an option. Instead, the global challenge is to steer reefs through the Anthropocene era in a way that maintains their biological functions. Successful navigation of this transition will require radical changes in the science, management and governance of coral reefs.


Assuntos
Aclimatação , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Recifes de Corais , Ecologia/métodos , Ecologia/tendências , Aquecimento Global/prevenção & controle , Aquecimento Global/estatística & dados numéricos , Atividades Humanas , Animais , Antozoários/fisiologia , Dióxido de Carbono/análise , Água do Mar/análise , Água do Mar/química
3.
Diabetes Spectr ; 35(3): 327-334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36082012

RESUMO

Background: Effective self-management of type 2 diabetes requires receiving support, which can result from disclosing the diagnosis to a support network, including coworkers, family, and friends. As a primarily invisible disease, diabetes allows people to choose whether to disclose. This study qualitatively explores the factors that influence a person's decision to disclose diabetes to others. Methods: Research coordinators recruited 22 interview participants, ranging in age from 32 to 64 years, whose medical records included a diagnosis code for type 2 diabetes. Participants received care from one of two U.S. medical centers. Semi-structured interviews lasted approximately 1 hour and were audio-recorded and professionally transcribed. Verification strategies such as memo-keeping and maintaining methodological coherence/congruence were used throughout analysis to promote rigor. Results: In patients' descriptions of their decision-making processes regarding whether to disclose their diagnosis, six themes emerged. Three motivations prompted open disclosure: 1) to seek information, 2) to seek social support, and 3) to end the succession of diabetes, and the other three motivations prompted guarded disclosure: 4) to prepare for an emergency, 5) to maintain an image of health, and 6) to protect employment. Conclusion: Based on our findings, we recommend three communicative actions for clinicians as they talk to patients about a diabetes diagnosis. First, clinicians should talk about the benefits of disclosure. Second, they should directly address stereotypes in an effort to de-stigmatize diabetes. Finally, clinicians can teach the skills of disclosure. As disclosure efficacy increases, a person's likelihood to disclose also increases. Individuals can use communication as a tool to gain the knowledge and support they need for diabetes self-management and to interrupt the continuing multigenerational development of diabetes within their family.

4.
Health Expect ; 24(4): 1187-1196, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33949058

RESUMO

BACKGROUND: Remission of diabetes can be rewarding for patients and physicians, but there is limited study of how patients perceive the timeline of a disease along the continuum of glycaemic control. OBJECTIVE: To explore how patients perceive the timeline of diabetes along the continuum of glycaemic control and their goals of care and to identify whether family physicians communicate the principles of regression and remission of diabetes. DESIGN: Mixed methods approach of qualitative semi-structured interviews with purposive sampling followed by cross-sectional survey of physicians. PARTICIPANTS: Thirty-three patients living with prediabetes (preDM) or type 2 diabetes mellitus (T2DM) at medical centres in Georgia and Nevada; and 387 family physicians providing primary care within the same health system. RESULTS: Patients described two timelines of diabetes: as a lifelong condition or as a condition that can be cured. Patients who perceived a lifelong condition described five treatment goals: reducing glucose-related laboratory values, losing weight, reducing medication, preventing treatment intensification and avoiding complications. For patients who perceived diabetes as a disease with an end, the goal of care was to achieve normoglycaemia. In response to patient vignettes that described potential cases of remission and regression, 38.2% of physician respondents would still communicate that a patient has preDM and 94.6% would tell the patient that he still had diabetes. CONCLUSIONS: Most physicians here exhibited reluctance to communicate remission or regression in patient care. Yet, patients describe two different potential timelines, including a subset who expect their diabetes can be 'cured'. Physicians should incorporate shared decision making to create a shared mental model of diabetes and its potential outcomes with patients. PATIENT OR PUBLIC CONTRIBUTION: In this mixed methods study, as patients participated in the qualitative phase of this study, we asked patients to tell us what additional questions we should ask in subsequent interviews. Data from this qualitative phase informed the design and interpretation of the quantitative phase with physician participants.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Estudos Transversais , Diabetes Mellitus Tipo 2/terapia , Humanos , Masculino , Percepção , Médicos de Família
6.
J Surg Res ; 240: 70-79, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30909067

RESUMO

BACKGROUND: Management of perforated appendicitis in children remains controversial. Nonoperative (NO) and immediate operative (IO) strategies are used with varying outcomes. We hypothesized that IO intervention for patients with perforated appendicitis would be more cost-effective than NO management. METHODS: A retrospective chart review of all patients with appendicitis from 2012 to 2015 was performed. Patients with perforated appendicitis were defined by evidence of perforation on imaging. We excluded patients who presented with sepsis, organ failure, and ventriculoperitoneal shunts. NO management was determined by surgeon preference. Univariate and multivariate analyses were performed. RESULTS: IO was performed on 145 patients with perforated appendicitis, whereas 83 were treated with NO management. Compared to IO patients, NO patients incurred higher overall costs, greater length of stay, more readmissions, complications, peripherally inserted central venous catheter lines, interventional radiology drains, and unplanned clinic and emergency department visits (P < 0.0001 for all). Multivariate analysis adjusting for age, days of symptoms, admission C-reactive protein and white blood cell count revealed that NO management was independently associated with increased costs (OR 1.35, 1.12-1.62, 95% CI). Cost curves demonstrated that total cost for IO surpasses that of NO management when patients present with greater than 6.3 d of symptoms (P = 0.01). CONCLUSIONS: Our data suggest that IO is more cost-effective than NO management for patients with perforated appendicitis who present with less than 6.3 d of symptoms, after which point, NO management is more cost-effective. LEVEL OF EVIDENCE: IV.


Assuntos
Antibacterianos/uso terapêutico , Apendicectomia/métodos , Apendicite/terapia , Análise Custo-Benefício , Perfuração Intestinal/terapia , Adolescente , Antibacterianos/economia , Apendicectomia/economia , Apendicectomia/estatística & dados numéricos , Apendicite/complicações , Apendicite/economia , Criança , Pré-Escolar , Drenagem/economia , Drenagem/estatística & dados numéricos , Feminino , Humanos , Lactente , Perfuração Intestinal/economia , Perfuração Intestinal/etiologia , Tempo de Internação/estatística & dados numéricos , Masculino , Estudos Retrospectivos , Fatores de Tempo , Tempo para o Tratamento
7.
Int J Cancer ; 143(6): 1483-1493, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29665011

RESUMO

Tumor-associated macrophages can promote growth of cancers. In neuroblastoma, tumor-associated macrophages have greater frequency in metastatic versus loco-regional tumors, and higher expression of genes associated with macrophages helps to predict poor prognosis in the 60% of high-risk patients who have MYCN-non-amplified disease. The contribution of cytotoxic T-lymphocytes to anti-neuroblastoma immune responses may be limited by low MHC class I expression and low exonic mutation frequency. Therefore, we modelled human neuroblastoma in T-cell deficient mice to examine whether depletion of monocytes/macrophages from the neuroblastoma microenvironment by blockade of CSF-1R can improve the response to chemotherapy. In vitro, CSF-1 was released by neuroblastoma cells, and topotecan increased this release. In vivo, neuroblastomas formed by subcutaneous co-injection of human neuroblastoma cells and human monocytes into immunodeficient NOD/SCID mice had fewer human CD14+ and CD163+ cells and mouse F4/80+ cells after CSF-1R blockade. In subcutaneous or intra-renal models in immunodeficient NSG or NOD/SCID mice, CSF-1R blockade alone did not affect tumor growth or mouse survival. However, when combined with cyclophosphamide plus topotecan, the CSF-1R inhibitor BLZ945, either without or with anti-human and anti-mouse CSF-1 mAbs, inhibited neuroblastoma growth and synergistically improved mouse survival. These findings indicate that depletion of tumor-associated macrophages from neuroblastomas can be associated with increased chemotherapeutic efficacy without requiring a contribution from T-lymphocytes, suggesting the possibility that combination of CSF-1R blockade with chemotherapy might be effective in patients who have limited anti-tumor T-cell responses.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Macrófagos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Animais , Apoptose , Benzotiazóis/farmacologia , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Humanos , Macrófagos/imunologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Monócitos/imunologia , Monócitos/patologia , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Ácidos Picolínicos/farmacologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Surg Res ; 229: 351-356, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29937013

RESUMO

BACKGROUND: With the advent of minimally invasive techniques, laparoscopic Ladd's procedure is increasingly used to treat children with malrotation, yet evidence regarding its safety and efficacy is lacking. We hypothesize that operative and postoperative outcomes with the open technique are superior to the laparoscopic Ladd's procedure. METHODS: We conducted a 5-y retrospective chart review of all patients who underwent Ladd's procedure at our institution from 2010-2015. Exclusion of patients included those with concomitant conditions, such as poor gut perfusion, significant reflux, tracheoesophageal fistula, failure to thrive requiring concomitant gastrostomy, and biliary atresia. Kruskal-Wallis and Mann-Whitney tests were used where appropriate. RESULTS: Between 2010 and 2015, of 130 patients who underwent Ladd's procedure, 77 met inclusion criteria. Sixty-two patients underwent initial open surgery, 15 patients underwent laparoscopy, seven of which were converted to open. Patients undergoing open surgery were younger compared to the laparoscopic groups. Thirty-three of the 77 malrotation patients (43%) presented with volvulus, 27 underwent open surgery, four had laparoscopic converted to open procedures, and two patients underwent laparoscopic Ladd's without incident. Laparoscopy resulted in increased operative time and clinic visits. Patients undergoing laparoscopic to open surgery had longer operative times, time to resume diet, and length of hospital stay. No difference was noted in complications among the groups. CONCLUSIONS: Although minimally invasive approaches are becoming increasingly used, no evidence supports laparoscopic superiority over open Ladd's procedure. We found that open surgery was associated with shorter operating times and fewer clinic visits. Furthermore, laparotomy remains the favored procedure for patients presenting with volvulus.


Assuntos
Conversão para Cirurgia Aberta/estatística & dados numéricos , Obstrução Intestinal/cirurgia , Volvo Intestinal/cirurgia , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Adolescente , Criança , Pré-Escolar , Humanos , Incidência , Lactente , Recém-Nascido , Obstrução Intestinal/etiologia , Volvo Intestinal/complicações , Intestinos/anormalidades , Intestinos/cirurgia , Laparoscopia/métodos , Tempo de Internação/estatística & dados numéricos , Duração da Cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
9.
Am Nat ; 190(1): 17-28, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28617632

RESUMO

Colonial animals commonly exhibit morphologically polymorphic modular units that are phenotypically distinct and specialize in specific functional tasks. But how and why these polymorphic modules have evolved is poorly understood. Across colonial invertebrates, there is wide variation in the degree of polymorphism, from none in colonial ascidians to extreme polymorphism in siphonophores, such as the Portuguese man-of-war. Bryozoa are a phylum of exclusively colonial invertebrates that uniquely exhibit almost the entire range of polymorphism, from monomorphic species to others that rival siphonophores in their polymorphic complexity. Previous approaches to understanding the evolution of polymorphism have been based on analyses of (1) the functional role of polymorphs or (2) presumed evolutionary costs and benefits based on evolutionary theory that postulates polymorphism should be evolutionarily sustainable only in more stable environments because polymorphism commonly leads to the loss of feeding and sexual competence. Here we use bryozoans from opposite shores of the Isthmus of Panama to revisit the environmental hypothesis by comparison of faunas from distinct oceanographic provinces that differ greatly in environmental variability, and we then examine the correlations between the extent of polymorphism in relation to patterns of ecological succession and variation in life histories. We find no support for the environmental hypothesis. Distributions of the incidence of polymorphism in the oceanographically unstable Eastern Pacific are indistinguishable from those in the more stable Caribbean. In contrast, the temporal position of species in a successional sequence is collinear with the degree of polymorphism because species with fewer types of polymorphs are competitively replaced by species with higher numbers of polymorphs on the same substrata. Competitively dominant species also exhibit patterns of growth that increase their competitive ability. The association between degrees of polymorphism and variations in life histories is fundamental to understanding of the macroevolution of polymorphism.


Assuntos
Meio Ambiente , Invertebrados , Polimorfismo Genético , Animais , Briozoários , Panamá
10.
J Surg Res ; 204(1): 109-13, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27451875

RESUMO

BACKGROUND: Although patients with peripheral neuroblastoma (NB; pelvic and thoracic) typically have better outcomes and less aggressive disease compared with patients with abdominal disease, little has been published with regard to the management and outcomes of patients with cervical NB. Herein, we sought to determine the characteristics of cervical neuroblastic tumors and the effect of extent of resection on survival and outcomes. METHODS: We performed a retrospective review of 325 children with neuroblastic tumors at Children's Hospital Los Angeles over a 15-y period (January 1990-February 2015). Data collected from the medical record included location of tumor, age at diagnosis, age at resection, extent of resection, chemotherapy course, International Neuroblastoma Staging System stage, histologic International Neuroblastoma Pathology Classification, and MYCN amplification, a poor prognostic marker. Outcome variables included postoperative complications and overall survival. RESULTS: Twelve patients (3.6%) were found to have cervical neuroblastic tumors (nine NBs, one ganglioneuroblastoma, and two ganglioneuromas). All had favorable histology, and none (0/12) had MYCN amplification. Of the NB patients, four of nine patients underwent resection, whereas the other five underwent biopsy followed by chemotherapy or observation alone. Of the 12 total patients, six underwent gross total resection, four (67%) of which developed complications. At a median follow-up of 4.4 y, there were no recurrences or deaths. CONCLUSIONS: Cervical neuroblastic tumors represent favorable lesions with good outcomes similar to other peripheral neuroblastic tumors. In our study, survival was excellent regardless of extent of tumor resection. Based on our data, we recommend a minimally aggressive surgical approach in managing children with cervical neuroblastic tumors.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/cirurgia , Neuroblastoma/diagnóstico , Neuroblastoma/cirurgia , Adolescente , Quimioterapia Adjuvante , Criança , Pré-Escolar , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Estadiamento de Neoplasias , Neuroblastoma/tratamento farmacológico , Neuroblastoma/mortalidade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
11.
Dermatol Online J ; 22(3)2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-27136624

RESUMO

BACKGROUND: Tinea capitis is caused by dermatophyte fungi that utilize keratin as a nutrient source.  Scalp erythema, scaling, andcrusting are typical signs of this disease.  Although most commonly seen in prepubescent children, tinea capitis can occur in adults. RESULTS: Endothrix tinea capitis owing to Trichophyton tonsurans commonly produces generalized scaling and localized perifollicular inflammation reminiscent of lichen planopilaris. Ectothrix tinea capitis owing to Microsporum sp. produces well- demarcated erythematous plaques suggestive of psoriasis. H&E stained biopsy specimens, KOH preparations or fungal cultures will confirm the diagnosis. CONCLUSION: Because of a low index of suspicion for tinea capitis in adults with scaling and alopecia, diagnosis and appropriate treatment are often delayed. Resistance to treatment for seborrheic dermatitis or psoriasis should prompt a KOH, fungal culture orbiopsy to confirm the diagnosis of tinea capitis and initiate systemic antifungal agents.


Assuntos
Pele/patologia , Tinha do Couro Cabeludo/patologia , Idoso , Antifúngicos/uso terapêutico , Feminino , Humanos , Naftalenos/uso terapêutico , Terbinafina , Tinha do Couro Cabeludo/diagnóstico , Tinha do Couro Cabeludo/tratamento farmacológico
13.
Phys Ther Sport ; 67: 19-24, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38457997

RESUMO

OBJECTIVE: To determine return to running criteria currently used by physiotherapists following anterior cruciate ligament (ACL) injury. DESIGN: Self-reported online international survey. METHODS: An online survey of physiotherapists across Australia, the Netherlands and France. RESULTS: A total of 476 respondants participated in the survey across Australia (n = 153), the Netherlands (n = 162), and France (n = 161). For return to running criteria following a non-operative approach, the majority of respondents chose swelling (40.55%, n = 193/476), pain (38.24%, n = 182/476), knee extensor strength (34.34%, n = 163/476), single leg squat (31.93%, n = 152/476) and knee flexor strength (29.83%, n = 142/476). After ACL reconstruction, the highest responses were also swelling (41.18%, n = 196/476), pain (37.18%, n = 177/476), knee extensor strength (37.18%, n = 177/476) and single leg squat (33.19%, n = 158/476). From the identified themes the most common cutoff variables were pain between 0 and 3/10, swelling < grade 1+ and limb symmetry on strength and hop tests >70 %. CONCLUSION: Physiotherapists in Australia, France, and the Netherlands use many different return to running criteria and most of them use more than one criterion. Despite this, there was little consensus on the cut-off physiotherapists use to apply these criteria.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Fisioterapeutas , Volta ao Esporte , Corrida , Humanos , Lesões do Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/reabilitação , Austrália , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Corrida/lesões , Corrida/fisiologia , Inquéritos e Questionários , Países Baixos , França , Masculino , Feminino , Adulto , Força Muscular/fisiologia
14.
Cell Microbiol ; 14(7): 1097-108, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22381134

RESUMO

The bacterial pathogens Listeria monocytogenes and enteropathogenic Escherichia coli (EPEC) generate motile actin-rich structures (comet tails and pedestals) as part of their infectious processes. Nexilin, an actin-associated protein and a component of focal adhesions, has been suggested to be involved in actin-based motility. To determine whether nexilin is commandeered during L. monocytogenes and EPEC infections, we infected cultured cells and found that nexilin is crucial for L. monocytogenes invasion as levels of internalized bacteria were significantly decreased in nexilin-targeted siRNA-treated cells. In addition, nexilin is a component of the machinery that drives the formation of L. monocytogenes comet tails and EPEC pedestals. Nexilin colocalizes with stationary bacteria and accumulates at the distal portion of comet tails and pedestals of motile bacteria. We also show that nexilin is crucial for efficient comet tail formation as cells pre-treated with nexilin siRNA generate malformed comet tails, whereas nexilin is dispensable during EPEC pedestal generation. These findings demonstrate that nexilin is required for efficient infection with invasive and adherent bacteria and is key to the actin-rich structures these microbes generate.


Assuntos
Actinas/metabolismo , Escherichia coli Enteropatogênica/metabolismo , Escherichia coli Enteropatogênica/patogenicidade , Listeria monocytogenes/metabolismo , Listeria monocytogenes/patogenicidade , Proteínas dos Microfilamentos/metabolismo , Linhagem Celular , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos
15.
Ecol Lett ; 15(6): 561-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22462739

RESUMO

Caribbean reef corals have declined precipitously since the 1980s due to regional episodes of bleaching, disease and algal overgrowth, but the extent of earlier degradation due to localised historical disturbances such as land clearing and overfishing remains unresolved. We analysed coral and molluscan fossil assemblages from reefs near Bocas del Toro, Panama to construct a timeline of ecological change from the 19th century-present. We report large changes before 1960 in coastal lagoons coincident with extensive deforestation, and after 1960 on offshore reefs. Striking changes include the demise of previously dominant staghorn coral Acropora cervicornis and oyster Dendrostrea frons that lives attached to gorgonians and staghorn corals. Reductions in bivalve size and simplification of gastropod trophic structure further implicate increasing environmental stress on reefs. Our paleoecological data strongly support the hypothesis, from extensive qualitative data, that Caribbean reef degradation predates coral bleaching and disease outbreaks linked to anthropogenic climate change.


Assuntos
Antozoários , Recifes de Corais , Fósseis , Moluscos , Mortalidade , Animais , Região do Caribe , Panamá , Dinâmica Populacional
16.
Small ; 8(10): 1534-42, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22419542

RESUMO

Very short arrays of continuous single-wall carbon nanotubes (SWNTs) are grown incrementally in steps as small as 25 nm using pulsed chemical vapor deposition (CVD). In-situ optical extinction measurements indicate that over 98% of the nanotubes reinitiate growth on successive gas pulses, and high-resolution transmission electron microscopy (HR-TEM) images show that the SWNTs do not exhibit segments, caps, or noticeable sidewall defects resulting from repeatedly stopping and restarting growth. Time-resolved laser reflectivity (3-ms temporal resolution) is used to record the nucleation and growth kinetics for each fast (0.2 s) gas pulse and to measure the height increase of the array in situ, providing a method to incrementally grow short nanotube arrays to precise heights. Derivatives of the optical reflectivity signal reveal distinct temporal signatures for both nucleation and growth kinetics, with their amplitude ratio on the first gas pulse serving as a good predictor for the evolution of the growth of the nanotube ensemble into a coordinated array. Incremental growth by pulsed CVD is interpreted in the context of autocatalytic kinetic models as a special processing window in which a sufficiently high flux of feedstock gas drives the nucleation and rapid growth phases of a catalyst nanoparticle ensemble to occur within the temporal period of the gas pulse, but without inducing growth termination.

17.
Sci Adv ; 8(13): eabp9344, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35353562

RESUMO

Bryozoans, simple invertebrates living on the sea floor, are emerging as a model system for understanding ecological and evolutionary processes on macroevolutionary scales.

18.
Prim Care Diabetes ; 16(3): 452-456, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35256315

RESUMO

AIMS: To investigate the effects of a curriculum that teaches medical decision making and interpersonal communication in the context of prediabetes (preDM) and type 2 diabetes (T2DM). METHODS: This evaluation was an active-controlled trial of 56 patients, including patients who received their diagnosis from intervention-trained clinicians or a control group. Patients attended a research appointment for informed consent and collection of baseline measures. Over the following six months, both groups were mailed surveys and informational handouts monthly. Upon conclusion, we recorded the most recent A1c from the patient's record. RESULTS: An analysis of covariance test revealed patients who received a T2DM diagnosis from an intervention-trained clinician reported higher reassurance from the diagnosing clinician and had a higher perception of threat. Although not statistically significant, patients with T2DM in the intervention group had a lower A1c at follow up and patients in the intervention group reported less poor eating and a higher degree of diet decision making. CONCLUSIONS: The curriculum itself does not influence glycemic control, but our results demonstrate the positive impact on patients of the curriculum to teach critical skills to clinicians delivering a diabetes diagnosis.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Currículo , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas , Humanos , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/terapia , Inquéritos e Questionários
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