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1.
Water Sci Technol ; 89(10): 2593-2604, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38822602

RESUMO

The number of published literature on the effect of ultrasonic cavitation and advanced oxidation pretreatment on the dewatering performance of anaerobically digested sludge is very limited. This study aims at determining the optimum operating conditions of large-scale filtering centrifuges in wastewater treatment plants. The optimum dose of hydrogen peroxide, ultrasonic power, ultrasonic duration, ultrasonic pulse and particle size distribution for improved dewatering performance were determined in this study. In addition, shear stress-shear rate and viscosity-shear rate rheograms were developed to show the rheological flow properties for varying ultrasonic power and treatment duration. Optimum sonication power, time, pulse and amplitude were determined to be 14 W, 1 min, 55/5 and 20%, respectively. At a pH of 6.8, the optimum concentration of hydrogen peroxide was found to be 43.5 g/L. The optimum hydrogen peroxide dose in the combined conditioning experiments was determined to be 500 mg/L at a pH of 3. Under these optimum conditions, capillary suction time was reduced significantly by 71.1%. This study helps to reduce polymer consumption and provides the optimum pretreatment and dewatering operating conditions, and better monitoring and control in the dewatering unit has significant impact in the overall economy of wastewater treatment plants.


Assuntos
Peróxido de Hidrogênio , Oxirredução , Esgotos , Eliminação de Resíduos Líquidos , Esgotos/química , Peróxido de Hidrogênio/química , Eliminação de Resíduos Líquidos/métodos , Ultrassom/métodos , Concentração de Íons de Hidrogênio
2.
J Am Chem Soc ; 142(28): 12193-12206, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32614174

RESUMO

The rational design of a new class of photoresponsive tris(8-hydroxyquinolinato)aluminum(III) (Alq3) complexes has been developed. By incorporating the photochromic dithienylethene units with different peripheral heterocycles into the Alq3 framework, the photochromic properties as well as photoswitching efficiency can be readily modulated, through effective photocyclization of the Al(III) complex. Such intrinsic photochromic behavior leads to the unprecedented enhancement in the electron-transporting properties as demonstrated by the as-fabricated electron-only device, rendering the realization of photoswitchable electron mobility. In addition, one of these complexes is capable of serving as an active layer for solution-processable resistive memory devices. Photocontrollable memory performance has been achieved with a binary memory behavior, with high ON/OFF ratio and long retention time. This work represents not only the first example of photoresponsive Alq3-based electron-transporting materials but also the solution-processable Alq3-based optical and resistive memory devices with photocontrollable performance.

3.
Clin J Sport Med ; 30(2): 91-95, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32000168

RESUMO

The American Medical Society for Sports Medicine convened a panel of experts to provide an evidence-based, best practice document to assist sports medicine physicians and other members of the athletic care network with the detection, treatment, and prevention of mental health (MH) issues in competitive athletes. This statement discusses how members of the sports medicine team, including team physicians, athletic trainers, and MH providers, work together in providing comprehensive psychological care to athletes. It specifically addresses psychological factors in athletes including personality issues and the psychological response to injury and illness. The statement also examines the athletic culture and environmental factors that commonly impact MH, including sexuality and gender issues, hazing, bullying, sexual misconduct, and transition from sport. Specific MH disorders in athletes, such as eating disorders/disordered eating, depression and suicide, anxiety and stress, overtraining, sleep disorders and attention-deficit/hyperactivity disorder, are reviewed with a focus on detection, management, the effect on performance, and prevention. This document uses the Strength of Recommendation Taxonomy to grade level of evidence.


Assuntos
Atletas/psicologia , Traumatismos em Atletas/psicologia , Comportamento de Doença , Transtornos Mentais/psicologia , Saúde Mental , Traumatismos em Atletas/prevenção & controle , Traumatismos em Atletas/terapia , Comportamento Competitivo , Meio Ambiente , Medicina Baseada em Evidências , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/prevenção & controle , Transtornos Mentais/terapia , Cultura Organizacional , Personalidade
4.
Clin J Sport Med ; 30(2): e61-e87, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32000169

RESUMO

The American Medical Society for Sports Medicine convened a panel of experts to provide an evidence-based, best practices document to assist sports medicine physicians and other members of the athletic care network with the detection, treatment, and prevention of mental health issues in competitive athletes. This statement discusses how members of the sports medicine team, including team physicians, athletic trainers, and mental health providers, work together in providing comprehensive psychological care to athletes. It specifically addresses psychological factors in athletes including personality issues and the psychological response to injury and illness. The statement also examines the athletic culture and environmental factors that commonly impact mental health, including sexuality and gender issues, hazing, bullying, sexual misconduct, and transition from sport. Specific mental health disorders in athletes, such as eating disorders/disordered eating, depression and suicide, anxiety and stress, overtraining, sleep disorders, and attention-deficit/hyperactivity disorder, are reviewed with a focus on detection, management, the effect on performance, and prevention. This document uses the Strength of Recommendation Taxonomy (SORT) to grade level of evidence.


Assuntos
Atletas/psicologia , Traumatismos em Atletas/psicologia , Comportamento de Doença , Transtornos Mentais/psicologia , Saúde Mental , Traumatismos em Atletas/prevenção & controle , Traumatismos em Atletas/terapia , Comportamento Competitivo , Meio Ambiente , Medicina Baseada em Evidências , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/prevenção & controle , Transtornos Mentais/terapia , Cultura Organizacional , Personalidade
5.
J Am Chem Soc ; 140(39): 12521-12526, 2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-30049208

RESUMO

A thermally activated delayed fluorescence (TADF) tetrametallic Cu(I) metallacycle A behaves as a conformationally adaptive preorganized precursor to afford, through straightforward and rational coordination-driven supramolecular processes, a variety of room-temperature solid-state luminescent polymetallic assemblies. Reacting various cyano-based building blocks with A, a homometallic Cu(I) 1D-helical coordination polymer C and Cu8M discrete circular heterobimetallic assemblies DM (M = Ni, Pd, Pt) are obtained. Their luminescence behaviors are studied, revealing notably the crucial impact of the spin-orbit coupling offered by the central M metal center on the photophysical properties of the heterobimetallic DM derivatives.

6.
Chemistry ; 24(6): 1383-1393, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29266490

RESUMO

A new class of phosphole oxide based alkynylplatinum(II) 2,6-bis(N-alkylbenzimidazol-2'-yl)pyridine (bzimpy) complexes were synthesized and characterized. Their self-assembly was driven by hydrophobic-hydrophobic and π-π stacking interactions. The self-assembly properties were also investigated by UV/Vis absorption spectroscopy, which revealed that the alkyl-chain length of the bzimpy moiety and the π-surface area of the alkynyl ligand have significant influence on the overall self-assembly process. The alkyl-chain length also affected the morphological structures of the aggregates, which were studied by transmission electron microscopy and scanning electron microscopy.

7.
Chemistry ; 24(45): 11611-11618, 2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-30063269

RESUMO

A series of bipyridine platinum(II) complexes with different sizes of triangular metallacycles and alkyl/oligoether chains has been synthesized and characterized. They are packed in a zig-zag fashion with the formation of dimeric structures according to their X-ray crystal structures. Different emission origins are observed due to the different sizes of the triangular ligands. Their morphologies could be tuned by the modification of the molecular structures with different metallacyclic alkynyl ligands and alkyl/oligoether chains and solvents. More interestingly, unusual electronic absorption changes and upfield shifts of the aromatic proton resonances are observed upon increasing the temperature, suggesting further aggregation of the architectures. Near-infrared (NIR) emission is also realized through the tuning of the π-π stacking, Pt⋅⋅⋅Pt interactions, and the packing of planar metallacycles.

8.
J Am Chem Soc ; 139(39): 13858-13866, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28933841

RESUMO

A series of amphiphilic platinum(II) complexes with tridentate N-donor ligands has been synthesized and characterized. Different supramolecular architectures are constructed using the amphiphilic molecules as the building blocks through the formation of Pt···Pt and π-π stacking interactions in aqueous media. The aggregation-deaggregation-aggregation self-assembly behavior together with obvious spectroscopic changes could be fine-tuned by the addition of THF in aqueous media. More interestingly, one of the complexes is found to show fast response and high selectivity toward alcohol and water vapors with good reversibility, leading to drastic color and luminescence changes, and hence unique dual switching behavior, with the water molecules readily displaced by the alcohol vapor. Rapid writing and erasure have been realized via the control of a jet or a stream of alcohol vapor flow. In addition, it has been employed as active materials in the fabrication of small-molecule solution-processable resistive memory devices, exhibiting stable and promising binary memory performance with threshold voltages of ca. 3.4 V, high ON/OFF ratios of up to 105 and long retention times of over 104 s. The vapochromic and vapoluminescent materials are demonstrated to have potential applications in chemosensing, logic gates, VOC monitoring, and memory functions.

9.
Soft Matter ; 13(45): 8408-8418, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29077127

RESUMO

A new class of small molecule-based amphiphilic carbazole-containing compounds has been designed and synthesized. Detailed analysis of the temperature- and solvent-dependent UV-vis absorption spectra has provided insights into the cooperative self-assembly mechanism of the carbazole-containing compounds. Interestingly, the prepared amphiphilic rigid-soft compounds were also found to display a lower critical solution temperature (LCST) behavior in aqueous solution, which is relatively less explored in small molecule-based materials, leading to promising candidates for the design of a new class of thermo-responsive materials.

10.
J Am Chem Soc ; 138(20): 6368-71, 2016 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-27163338

RESUMO

A novel class of luminescent phosphole oxide-containing alkynylgold(III) complex has been synthesized, characterized, and applied as active material in the fabrication of solution-processable resistive memory devices. Incorporation of the phosphole oxide moiety in gold(III) system has been demonstrated to provide an extra charge-trapping site, giving rise to intriguing ternary memory performances with distinct and low switching threshold voltages, high OFF/ON1/ON2 current ratio of 1/10(3)/10(7), and long retention time for the three states. The present study offers vital insights for the future development of multilevel memory devices using small-molecule organometallic compounds.

11.
Br J Sports Med ; 50(3): 167-71, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26782764

RESUMO

BACKGROUND: There are approximately 400,000 National Collegiate Athletic Association (NCAA) student athletes and 5-7 million high school student athletes competing each year. According to the US Department of Health and Human Services, the depression prevalence rate for young adults, which ranges from 10% to 85% across studies, is higher than that of other age groups. Given the relatively high prevalence of depression in individuals of collegiate age in the general population, the prevalence of depression among athletes in this age group warrants further study. This multiyear study examined the prevalence of depressive symptoms in college athletes, as well as demographic factors related to increased or decreased rates of depressive symptoms by gender and sport. OBJECTIVE: To describe the prevalence of depression symptoms among NCAA division I student athletes at a single institution over 3 consecutive years. METHOD: Participants (n=465) completed a battery of measures during their yearly spring sports medicine physical across 3 consecutive years. The battery included the Center for Epidemiological Studies Depression Scale (CES-D) and a demographic questionnaire, administered during the course of routine sports medicine physical examinations. Differences in depressive symptoms prevalence and relative risk ratios were calculated by gender and sport. RESULTS: The prevalence rate for a clinically relevant level of depressive symptoms, as measured on the CES-D (CES-D ≥16), was 23.7%. A moderate to severe level of depressive symptoms was reported by 6.3%. There was a significant gender difference in prevalence of depressive symptoms, χ(2) (1)=7.459, p=0.006, with female athletes exhibiting 1.844 times the risk of male athletes for endorsing clinically relevant symptoms. CONCLUSIONS: The CES-D identified clinically relevant levels of depressive symptoms in nearly one-quarter of college student athletes in this large cross-sectional sample. Female college athletes reported significantly more depressive symptoms than males. Findings suggest that depression prevalence among college athletes is comparable to that found in the general college population. In light of these findings, sports medicine personnel may wish to implement depression screening and assessment of depressive symptoms across sports to identify at-risk athletes. Risk factors related to depression in college athletes warrant additional study.


Assuntos
Atletas/psicologia , Depressão/epidemiologia , Esportes/estatística & dados numéricos , Atletas/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Estados Unidos , Universidades
12.
Chemistry ; 21(15): 5732-5, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25707360

RESUMO

A series of luminescent polynuclear alkynylgold(I) complexes with different lengths of alkyl chains attached at the N-heterocyclic carbene moieties has been synthesised and demonstrated to display intriguing self-assembly behaviours through a cooperative growth mechanism. Variation of the alkyl chain length was found to cause drastic morphological differences in the aggregates and to strongly affect the thermodynamic parameters as revealed by the nucleation-elongation model.

13.
Curr Sports Med Rep ; 14(1): 56-60, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25574886

RESUMO

Depression affects an estimated 6.7% of today's adult population in a 12-month period. The prevalence rates for certain age groups, such as young adults and older adults, are higher. There are approximately 400,000 National Collegiate Athletic Association student athletes competing each year and 5 to 7 million high school student athletes involved in competitive interscholastic sports. Given such a high prevalence rate in certain age groups and a large denominator pool of athletes, past notions that athletes are devoid of mental health issues have come under scrutiny by sports medicine providers. Initial data suggest that athletes are far from immune to depression. The purpose of this article was to review the current research on athletes and depression; particularly this article will provide an overview of studies, which have investigated the rate of depression among athletes, and discuss relevant risk factors, which may contribute to depression among athletes.


Assuntos
Atletas/psicologia , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/psicologia , Depressão/epidemiologia , Depressão/psicologia , Traumatismos em Atletas/diagnóstico , Escolha da Profissão , Depressão/diagnóstico , Humanos , Prevalência , Fatores de Risco , Medicina Esportiva/tendências , Suicídio/psicologia , Prevenção do Suicídio
14.
Curr Sports Med Rep ; 13(2): 86-93, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24614421

RESUMO

Abdominal hernias are common with over 20 million hernia repairs performed worldwide. Inguinal hernias are the most common type of hernia. Inguinal and sports hernia have been discussed at length in recent literature, and therefore, they will not be addressed in this article. The noninguinal hernias are much less common but do occur, and knowledge of these hernias is important when assessing the athlete with abdominal pain. Approximately 25% of abdominal wall hernias are noninguinal, and new data show the order of frequency as umbilical, epigastric, incisional, femoral, and all others (i.e., Spigelian, obturator, traumatic). Return-to-play guidelines need to be tailored to the athlete and the needs of their sport. Using guidelines similar to abdominal strain injuries can be a starting point for the treatment plan. Laparoscopic repair is becoming more popular because of safety and efficacy, and it may lead to a more rapid return to play.


Assuntos
Atletas , Traumatismos em Atletas/terapia , Compreensão , Guias como Assunto/normas , Hérnia Abdominal/terapia , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/epidemiologia , Feminino , Hérnia Abdominal/diagnóstico , Hérnia Abdominal/epidemiologia , Humanos , Masculino
15.
Curr Sports Med Rep ; 12(1): 33-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23314082

RESUMO

The understanding of paraneoplastic syndromes has improved over the last several years. These disorders are brought about by tumor secretion of substances that can alter hormonal function and create immune cross-reactivity with normal tissues. This, in turn, can alter normal metabolic pathways resulting in paraneoplastic syndromes. The athlete must maintain an awareness of their body because these syndromes affect diverse organ systems. Commonly associated malignancies include small cell lung cancer, breast cancer, gynecologic tumors, and gastroenterological malignancies. These cancers most notably affect the neuromuscular, rheumatologic, mucocutaneous, hematologic, renal, and endocrine systems. Effective diagnosis and treatment of paraneoplastic syndromes most often require appropriate diagnosis and treatment of the underlying malignancy. This review focuses on the most commonly encountered paraneoplastic syndromes, so athletes and those who care for them can be aware of the potential risk of an occult or recurrent malignancy.


Assuntos
Síndromes Paraneoplásicas/diagnóstico , Síndromes Paraneoplásicas/terapia , Educação de Pacientes como Assunto/métodos , Esportes , Humanos
16.
Curr Sports Med Rep ; 11(2): 92-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22410701

RESUMO

Individuals involved in sports are at risk for sustaining various injuries. In addition to musculoskeletal complaints, male athletes are at risk of incurring testicular injuries. These issues can range from an acute emergency such as testicular torsion to indolent testicular tumors. In contrast, epididymitis can present in stages. Presentation and management of testicular complaints can vary depending on the condition. Physicians who provide medical care to athletes need to be competent in diagnosing and managing testicular injuries.


Assuntos
Epididimite/diagnóstico , Torção do Cordão Espermático/diagnóstico , Doenças Testiculares/diagnóstico , Antibacterianos/uso terapêutico , Atletas , Epididimite/tratamento farmacológico , Humanos , Masculino , Torção do Cordão Espermático/cirurgia , Doenças Testiculares/cirurgia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/cirurgia , Testículo/anatomia & histologia , Testículo/fisiologia
18.
Chem Commun (Camb) ; 57(100): 13708-13711, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34842259

RESUMO

The enhanced supramolecular self-assembly behaviors of photo-caged platinum(II) complexes have been triggered by applying light as the external stimulus. Distinct morphological transformation of the nanoaggregates has been observed in the photo-caged complexes before and after UV irradiation.

19.
Chem Asian J ; 16(22): 3669-3676, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34569719

RESUMO

A series of heteroleptic cyclometalated platinum(II) complexes, [Pt(C^N)(O^O)], (1-10) with various donors and acceptors has been synthesized and characterized by 1 H NMR spectroscopy, elemental analyses, infrared spectroscopy and mass spectrometry. The X-ray structure of 2 has also been determined. The electrochemical and photophysical properties of the platinum(II) complexes were studied. These experimental results have been supported by computational studies. Furthermore, two of the complexes have been employed as the active material in the fabrication of resistive memory devices, exhibiting stable binary memory performance with low operating voltage, high ON/OFF ratio and long retention time.

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