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1.
J Clin Child Adolesc Psychol ; : 1-14, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38270579

RESUMO

OBJECTIVE: Researchers employed two recruitment strategies in a school-based comparative effectiveness trial for students with a diagnosis of attention-deficit/hyperactivity disorder (ADHD) or autism. This study assessed the: 1) effectiveness of school-based referrals for identifying students meeting diagnostic criteria and 2) impact of eliminating requirements for existing diagnoses on recruitment, sample characteristics, and intervention response. METHOD: Autistic students and students with ADHD in schools serving underresourced communities were recruited for an executive functioning (EF) intervention trial over 2 years. In Year 1, school staff nominated students with previous diagnoses. In Year 2, school staff nominated students demonstrating EF challenges associated with ADHD or autism; previous diagnosis was not required. Study staff then confirmed diagnoses. RESULTS: More students were included in Year 2 (N = 106) than Year 1 (N = 37). In Year 2, 96% of students referred by school staff met diagnostic criteria for ADHD or autism, 53% of whom were not previously diagnosed. Newly identified students were less likely than previously diagnosed students to be receiving services and, for those with ADHD, were more likely to speak primarily Spanish at home. Previously diagnosed and newly identified students did not differ on other demographic variables or intervention response. Caregivers of previously diagnosed students reported more symptoms than caregivers of newly identified students for both diagnostic groups. Previously diagnosed students with ADHD had more researcher-rated symptoms than newly identified students. CONCLUSIONS: Recruitment for an intervention study using behavior-based referrals from school staff enhanced enrollment without compromising the sample's diagnostic integrity and engaged children who otherwise would have been excluded.

2.
Phys Rev Lett ; 129(18): 183603, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36374670

RESUMO

The crossover from quantum to semiclassical behavior in the seminal Rabi model of light-matter interaction still, surprisingly, lacks a complete and rigorous understanding. A formalism for deriving the semiclassical model directly from the quantum Hamiltonian is developed here. Working in a displaced Fock-state basis |α,n⟩, the semiclassical limit is obtained by taking |α|→∞ and the coupling to zero. This resolves the discrepancy between coherent-state dynamics and semiclassical Rabi oscillations in both standard and ultrastrong coupling and driving regimes. Furthermore, it provides a framework for studying the quantum-to-semiclassical transition, with potential applications in quantum technologies.

3.
Nat Commun ; 12(1): 6182, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702813

RESUMO

The nature of the quantum-to-classical crossover remains one of the most challenging open question of Science to date. In this respect, moving objects play a specific role. Pioneering experiments over the last few years have begun exploring quantum behaviour of micron-sized mechanical systems, either by passively cooling single GHz modes, or by adapting laser cooling techniques developed in atomic physics to cool specific low-frequency modes far below the temperature of their surroundings. Here instead we describe a very different approach, passive cooling of a whole micromechanical system down to 500 µK, reducing the average number of quanta in the fundamental vibrational mode at 15 MHz to just 0.3 (with even lower values expected for higher harmonics); the challenge being to be still able to detect the motion without disturbing the system noticeably. With such an approach higher harmonics and the surrounding environment are also cooled, leading to potentially much longer mechanical coherence times, and enabling experiments questioning mechanical wave-function collapse, potentially from the gravitational background, and quantum thermodynamics. Beyond the average behaviour, here we also report on the fluctuations of the fundamental vibrational mode of the device in-equilibrium with the cryostat. These reveal a surprisingly complex interplay with the local environment and allow characteristics of two distinct thermodynamic baths to be probed.

5.
Am J Intellect Dev Disabil ; 123(6): 514-528, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30421968

RESUMO

The cause of the high degree of variability in cognition and behavior among individuals with Down syndrome (DS) is unknown. We hypothesized that birth defects requiring surgery in the first years of life (congenital heart defects and gastrointestinal defects) might affect an individual's level of function. We used data from the first 234 individuals, age 6-25 years, enrolled in the Down Syndrome Cognition Project (DSCP) to test this hypothesis. Data were drawn from medical records, parent interviews, and a cognitive and behavior assessment battery. Results did not support our hypothesis. That is, we found no evidence that either birth defect was associated with poorer outcomes, adjusting for gender, race/ethnicity, and socioeconomic status. Implications for study design and measurement are discussed.


Assuntos
Sintomas Comportamentais/epidemiologia , Disfunção Cognitiva/epidemiologia , Anormalidades do Sistema Digestório/epidemiologia , Síndrome de Down/epidemiologia , Cardiopatias Congênitas/epidemiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Adulto Jovem
7.
Pharmacogenomics J ; 18(3): 480-486, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-28786423

RESUMO

HLA-DRB1*07:01 allele carriage was characterised as a risk biomarker for lapatinib-induced liver injury in a large global study evaluating lapatinib, alone and in combination with trastuzumab and taxanes, as adjuvant therapy for advanced breast cancer (adjuvant lapatinib and/or trastuzumab treatment optimisation). HLA-DRB1*07:01 carriage was associated with serum alanine aminotransferase (ALT) elevations in lapatinib-treated patients (odds ratio 6.5, P=3 × 10-26, n=4482) and the risk and severity of ALT elevation for lapatinib-treated patients was higher in homozygous than heterozygous HLA-DRB1*07:01 genotype carriers. A higher ALT case incidence plus weaker HLA association observed during concurrent administration of lapatinib and taxane suggested a subset of liver injury in this combination group that was HLA-DRB1*07:01 independent. Furthermore, the incidence of ALT elevation demonstrated an expected correlation with geographic HLA-DRB1*07:01 carriage frequency. Robust ALT elevation risk estimates for HLA-DRB1*07:01 may support causality discrimination and safety risk management during the use of lapatinib combination therapy for the treatment of metastatic breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/genética , Cadeias HLA-DRB1/genética , Lapatinib/efeitos adversos , Alelos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/complicações , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Lapatinib/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/patologia , Estadiamento de Neoplasias , Fatores de Risco , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Trastuzumab/administração & dosagem , Trastuzumab/efeitos adversos
8.
Ann Oncol ; 28(1): 128-135, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28177460

RESUMO

Background: We performed whole-exome sequencing of pretreatment biopsies and examined whether genome-wide metrics of overall mutational load, clonal heterogeneity or alterations at variant, gene, and pathway levels are associated with treatment response and survival. Patients and Methods: Two hundred and three biopsies from the NeoALTTO trial were analyzed. Mutations were called with MuTect, and Strelka, using pooled normal DNA. Associations between DNA alterations and outcome were evaluated by logistic and Cox-proportional hazards regression. Results: There were no recurrent single gene mutations significantly associated with pathologic complete response (pCR), except PIK3CA [odds ratio (OR) = 0.42, P = 0.0185]. Mutations in 33 of 714 pathways were significantly associated with response, but different genes were affected in different individuals. PIK3CA was present in 23 of these pathways defining a 'trastuzumab resistance-network' of 459 genes. Cases with mutations in this network had low pCR rates to trastuzumab (2/50, 4%) compared with cases with no mutations (9/16, 56%), OR = 0.035; P < 0.001. Mutations in the 'Regulation of RhoA activity' pathway were associated with higher pCR rate to lapatinib (OR = 14.8, adjusted P = 0.001), lapatinib + trastuzumab (OR = 3.0, adjusted P = 0.09), and all arms combined (OR = 3.77, adjusted P = 0.02). Patients (n = 124) with mutations in the trastuzumab resistance network but intact RhoA pathway had 2% (1/41) pCR rate with trastuzumab alone (OR = 0.026, P = 0.001) but adding lapatinib increased pCR rate to 45% (17/38, OR = 1.68, P = 0.3). Patients (n = 46) who had no mutations in either gene set had 6% pCR rate (1/15) with lapatinib, but had the highest pCR rate, 52% (8/15) with trastuzumab alone. Conclusions: Mutations in the RhoA pathway are associated with pCR to lapatinib and mutations in a PIK3CA-related network are associated with resistance to trastuzumab. The combined mutation status of these two pathways could define patients with very low response rate to trastuzumab alone that can be augmented by adding lapatinib or substituting trastuzumab with lapatinib.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Quinazolinas/uso terapêutico , Receptor ErbB-2/antagonistas & inibidores , Trastuzumab/uso terapêutico , Biópsia por Agulha Fina/métodos , Neoplasias da Mama/enzimologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , DNA de Neoplasias/genética , Feminino , Humanos , Lapatinib , Terapia de Alvo Molecular , Mutação , Modelos de Riscos Proporcionais , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinas/administração & dosagem , Trastuzumab/administração & dosagem , Sequenciamento do Exoma , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
9.
Phys Rev Lett ; 111(24): 247001, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24483692

RESUMO

We analyze the quantum dynamics of a superconducting cavity coupled to a voltage-biased Josephson junction. The cavity is strongly excited at resonances where the voltage energy lost by a Cooper pair traversing the circuit is a multiple of the cavity photon energy. We find that the resonances are accompanied by substantial squeezing of the quantum fluctuations of the cavity over a broad range of parameters and are able to identify regimes where the fluctuations in the system take on universal values.

10.
Eur Respir Rev ; 19(117): 186-96, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20956191

RESUMO

As the first approved epidermal growth factor receptor (EGFR)-targeted therapy for nonsmall cell lung cancer (NSCLC), the clinical development of gefitinib was complex. Advances in scientific understanding of the target biology during its clinical development enabled the identification of a biomarker to define patients most likely to derive benefit from gefitinib. Initial phase II trials showed clinically meaningful anti-tumour activity in 12-18% of unselected pretreated patients with advanced NSCLC at the optimum biological dose (250 mg). Subgroup analyses of these and subsequent phase III trials in unselected patients suggested that EGFR mutation and some clinical characteristics associated with a higher incidence of EGFR mutation (Asian ethnicity, adenocarcinoma histology, never-smoking and female sex) were linked with increased response to gefitinib. Consequently, the IRESSA Pan-Asia Study (IPASS) was conducted in never-smokers or former light-smokers in East Asia who had adenocarcinoma of the lung. IPASS showed that EGFR mutation was the strongest predictor of improved progression-free survival (mutation-positive subgroup hazard ratio (HR) 0.48, 95% CI 0.36-0.64 (p<0.001, n = 261); mutation-negative subgroup HR 2.85, 95% CI 2.05-3.98 (p<0.001, n = 176); interaction test p<0.001) with gefitinib versus carboplatin/paclitaxel as first-line therapy for advanced NSCLC. Important lessons for the development of future personalised medicines are discussed.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Quinazolinas/uso terapêutico , Gefitinibe , Humanos , Medicina de Precisão
11.
Phys Rev Lett ; 104(5): 053601, 2010 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-20366761

RESUMO

We analyze the amplitude and phase noise of limit-cycle oscillations in a mechanical resonator coupled parametrically to an optical cavity driven above its resonant frequency. At a given temperature the limit-cycle oscillations have lower amplitude noise than states of the same average amplitude excited by a pure harmonic drive; for sufficiently low thermal noise a sub-Poissonian resonator state can be produced. We also calculate the linewidth narrowing that occurs in the limit-cycle states and show that while the minimum is set by direct phase diffusion, diffusion due to the optical spring effect can dominate if the cavity is not driven exactly at a sideband resonance.

12.
Phys Rev Lett ; 98(6): 067204, 2007 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-17358982

RESUMO

We investigate the behavior of a quantum resonator coupled to a superconducting single-electron transistor (SSET) tuned to the Josephson quasiparticle resonance and show that the dynamics is similar in many ways to that found in a micromaser. Coupling to the SSET can drive the resonator into nonclassical states of self-sustained oscillation via either continuous or discontinuous transitions. Increasing the coupling further leads to a sequence of transitions and regions of multistability.

13.
Nature ; 443(7108): 193-6, 2006 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-16971944

RESUMO

Quantum mechanics demands that the act of measurement must affect the measured object. When a linear amplifier is used to continuously monitor the position of an object, the Heisenberg uncertainty relationship requires that the object be driven by force impulses, called back-action. Here we measure the back-action of a superconducting single-electron transistor (SSET) on a radio-frequency nanomechanical resonator. The conductance of the SSET, which is capacitively coupled to the resonator, provides a sensitive probe of the latter's position; back-action effects manifest themselves as an effective thermal bath, the properties of which depend sensitively on SSET bias conditions. Surprisingly, when the SSET is biased near a transport resonance, we observe cooling of the nanomechanical mode from 550 mK to 300 mK--an effect that is analogous to laser cooling in atomic physics. Our measurements have implications for nanomechanical readout of quantum information devices and the limits of ultrasensitive force microscopy (such as single-nuclear-spin magnetic resonance force microscopy). Furthermore, we anticipate the use of these back-action effects to prepare ultracold and quantum states of mechanical structures, which would not be accessible with existing technology.

14.
Theriogenology ; 66(6-7): 1513-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16488001

RESUMO

UNLABELLED: The objectives of this study were to confirm: (i) whether progestin treatment suppressed GnRH agonist-induced estrus in anestrous greyhound bitches; and (ii) the site of progestin action (i.e. pituitary, ovary). All bitches received a deslorelin implant on Day 0 and blood samples were taken from -1 h to +6 h. Five bitches were treated with megestrol acetate (2 mg/kg orally once daily) from -7 d to +6 d (Group 1) and 10 bitches were untreated controls (Group 2). Proestrous or estrous signs were observed in 4 of 5 bitches in Group 1, and 4 of 10 bitches in Group 2 (P = 0.28). The plasma LH responses (area under the curve from 0 to 6h after implantation) were higher (P = 0.008) in Group 2 than in Group 1. Plasma LH responses were similar (P = 0.59) in bitches showing signs of proestrus or estrus (responders) and in non-responders. The plasma estradiol responses (calculated as for LH response) were greater in Group 1 than in Group 2 (P = 0.048), and in responders than in non-responders (P = 0.02). IN CONCLUSION: (i) progestin treatment (a) did not suppress the incidence of bitches showing deslorelin-induced proestrus or estrus, and (b) was associated with a reduced pituitary responsiveness and an increased ovarian responsiveness to deslorelin treatment; (ii) the occurrence of proestrous or estrous signs reflected increased ovarian responsiveness to induced gonadotrophin secretion and not increased pituitary responsiveness to deslorelin.


Assuntos
Anestro/fisiologia , Cães/fisiologia , Estradiol/sangue , Hormônio Luteinizante/sangue , Progestinas/farmacologia , Pamoato de Triptorrelina/análogos & derivados , Anestro/efeitos dos fármacos , Animais , Cães/sangue , Implantes de Medicamento , Estro/efeitos dos fármacos , Estro/fisiologia , Feminino , Acetato de Megestrol/farmacologia , Progesterona/sangue , Pamoato de Triptorrelina/administração & dosagem , Pamoato de Triptorrelina/antagonistas & inibidores , Pamoato de Triptorrelina/farmacologia
17.
Phys Rev Lett ; 88(14): 148301, 2002 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-11955180

RESUMO

We analyze the quantum dynamics of a micromechanical resonator capacitively coupled to a Cooper-pair box. With appropriate quantum state control of the Cooper box, the resonator can be driven into a superposition of spatially separated states. The Cooper box can also be used to probe the decay of the resonator superposition state due to environmental decoherence.

18.
Plast Reconstr Surg ; 108(2): 343-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11496172

RESUMO

The superwet technique has been shown in previous studies to dramatically reduce blood loss in breast reduction surgery, compared with standard infiltration. A retrospective chart review of 303 consecutive patients undergoing bilateral breast reduction surgery was undertaken to demonstrate additional differences in complication rate, operative time, or sponge use in the operating room. In this series, 132 consecutive patients received standard infiltration along incision lines (25 cc per breast of 1:100,000 epinephrine), and 171 patients received superwet infiltration with 240 cc per breast of 1:1,000,000 epinephrine. The average operative time was significantly reduced in the superwet group, from 78.5 minutes to 70.7 minutes (p < 0.01 level). The average number of sponges used intraoperatively was also decreased significantly (p < 0.01), from 26 to 20 sponges. Complication rates were equally low in both groups, demonstrating the safety of the superwet technique. In addition to limiting blood loss, the superwet infiltration effectively reduces operative time and sponge use without increasing complications in breast reduction surgery.


Assuntos
Anestesia Local , Epinefrina/administração & dosagem , Hemostasia Cirúrgica , Mamoplastia/métodos , Vasoconstritores/administração & dosagem , Adulto , Anestésicos Locais/administração & dosagem , Perda Sanguínea Cirúrgica/prevenção & controle , Feminino , Humanos , Lidocaína/administração & dosagem , Mamoplastia/efeitos adversos , Complicações Pós-Operatórias , Estudos Retrospectivos
19.
J Reprod Fertil Suppl ; 57: 263-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11787160

RESUMO

Studies were undertaken in Australia and Belgium to determine whether the initial pro-oestrous-oestrous responses of anoestrous bitches to treatment with deslorelin administered in a s.c. implant were inhibited by progestin treatment. Thirty-nine bitches of mixed breeding were treated daily with 2 mg megestrol acetate kg-1 body weight for 21 (group 1, n = 5) or 14 days (group 2, n = 10), or with 1 mg megestrol acetate kg-1 body weight for 14 days (group 3, n = 10). A deslorelin (6 mg) implant was placed s.c. on day 14 (group 1) or day 7 (groups 2 and 3) of treatment. Bitches not treated with progestin also received a deslorelin implant (group 4, n = 9) or were untreated controls (group 5, n = 9). Signs of pro-oestrus-oestrus were not observed in bitches in groups 1, 2 and 5, but were observed in bitches in groups 3 (4/10) and 4 (9/9). Four bitches in group 4 were mated, two of which became pregnant. The pregnancies failed at about day 40 of gestation and were associated with low plasma progesterone concentrations. Treatment with progestin inhibited the pro-oestrous-oestrous responses of bitches to deslorelin.


Assuntos
Anticoncepcionais/administração & dosagem , Cães , Estro/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/administração & dosagem , Acetato de Megestrol/administração & dosagem , Animais , Depressão Química , Implantes de Medicamento , Estradiol/sangue , Feminino , Gravidez , Progesterona/antagonistas & inibidores , Progesterona/sangue , Fatores de Tempo , Pamoato de Triptorrelina/análogos & derivados
20.
J Reprod Fertil Suppl ; 57: 255-61, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11787159

RESUMO

Continuous low-dose administration of a GnRH analogue postpones oestrus in bitches and suppresses reproductive function in dogs. A new drug delivery formulation that could enhance the practicality of this approach for the control of reproduction has been developed. The objective of the present study was to determine whether this method of delivery could, by sustained release of the GnRH analogue deslorelin, act as a reversible anti-fertility agent in domestic male and female dogs for periods exceeding 1 year. Several long-term studies were performed, which monitored reproductive function in 30 dogs and 52 bitches. Suppression of reproductive function in male dogs was dose-related. Spermatogenesis was suppressed for more than a year in 14 of 16 dogs that received doses of > 0.25 mg deslorelin kg-1. In females, postponement of oestrus for periods of up to 27 months was observed, but there was no relationship between the stage of the oestrous cycle at the start of treatment and the duration of efficacy. Treatment-induced effects on fertility were reversible in both sexes. In summary, sustained release deslorelin implants were shown to elicit reversible long-term reproductive control in male and female domestic dogs.


Assuntos
Anticoncepção/veterinária , Anticoncepcionais/administração & dosagem , Cães , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/administração & dosagem , Animais , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Masculinos/administração & dosagem , Relação Dose-Resposta a Droga , Implantes de Medicamento , Estro/efeitos dos fármacos , Feminino , Masculino , Espermatogênese/efeitos dos fármacos , Pamoato de Triptorrelina/análogos & derivados
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