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1.
J Appl Microbiol ; 131(5): 2567-2578, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33884721

RESUMO

AIMS: Assess the feasibility of using light from artificial sun lamps to decontaminate N95 filtering facepiece respirators (FFRs) contaminated with SARS-CoV-2. METHODS AND RESULTS: FFR coupons or whole FFRs contaminated with 5 log10 TCID50 (target concentration) SARS-CoV-2 in culture media, simulated saliva, or simulated lung fluid were dried for 1-2 h, then exposed to light from tanning and horticulture lamps to assess decontamination. Exposed coupons and whole FFRs showed SARS-CoV-2 inactivation for all matrices tested. Furthermore, FFRs still met performance specifications after five decontamination cycles. CONCLUSIONS: It is feasible that artificial sunlight from these sun lamps can be used to decontaminate FFRs provided the UV dose is sufficient and the light is unobstructed. Furthermore, decontamination can be performed up to five times without degrading FFR performance. SIGNIFICANCE AND IMPACT OF THE STUDY: This research shows a proof of principle that artificial sun lamps may be an option to decontaminate SARS-CoV-2 on N95 FFRs. UV doses required for inactivation to levels below detection ranged from 4 to 37·8 J cm-2 depending on the light source, virus matrix and FFR type.


Assuntos
COVID-19 , Reutilização de Equipamento , Descontaminação , Humanos , Respiradores N95 , SARS-CoV-2
2.
J Dairy Sci ; 104(3): 3327-3338, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33358814

RESUMO

Dairy cows housed in tiestalls are restricted to one space; therefore, this space should be designed to accommodate all the activities cows need to perform. Lying is a very important behavior for dairy cows as well as a critical measure in the assessment of stall designs, to ensure that the cows' needs for resting space are met. The objective of this study was to determine if increasing tiestall width alters the lying behavior of lactating dairy cows. Two treatments were compared: the current recommendation (139 cm) and a double stall (284 cm). Sixteen cows were blocked by parity and lactation stage, then randomly allocated to a treatment and a stall within 1 of 2 rows in the research barn, for 6 wk. The average stall length was 188 cm. Leg-mounted accelerometers were used to record lying behaviors. Cows were video-recorded 24 h/wk using surveillance cameras positioned above the stalls. Video data from wk 1, 3, and 6 were extracted at a rate of 1 image/min and analyzed by a trained observer to assess the position and the location of the cow's body, head, and limbs during the lying hours. Lying behaviors and frequency of each position and location were analyzed in SAS (SAS Institute Inc., Cary, NC) using a mixed model in which treatment, block, and week were included as fixed factors, and cow and row as random factors. Multiple comparisons were adjusted using the Scheffé method. Results indicate that cows in double stalls fully extended their hindlimbs more often than single stall cows (21.7 vs. 7.6% of lying time). Cows in double stalls also intruded in the neighboring stalls with their hindlimbs less often (1.3 vs. 14.7% of lying time), instead positioning them inside their own stall more often (92.7 vs. 84.6% of lying time). Use of the second stall in the double stall group totaled 11.6, 5.1, 33.8, and 18.0% of lying time, respectively, for the head, front legs, hind legs, and body. Total lying time was not statistically different between double (716 min/d) and single stall (671 min/d) groups. Contacts with stall hardware during lying-down movements were also less frequent in double stalls (43.1 vs. 77.1% of lying events) compared with single stalls. These results suggest that dairy cows housed in double stalls modified their resting habits and used the extra space made available to them. Increasing stall width beyond the current recommendation is likely to benefit the cows by improving their ability to rest.


Assuntos
Indústria de Laticínios , Lactação , Animais , Comportamento Animal , Bovinos , Feminino , Abrigo para Animais , Paridade , Gravidez
3.
Exp Lung Res ; 46(1-2): 32-43, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31941389

RESUMO

Airway inflammation (assessed by exhaled nitric oxide (eNO)) increases after a single high-fat meal (HFM), yet this response may be modified by airway stretch and baseline eNO level.Purpose: The purpose of this study was to investigate whether deep inspirations (DIs) would attenuate airway inflammation post-HFM and whether this is modulated by baseline eNO level.Methods: A total of sixteen healthy college-aged participants completed a randomized cross-over study with 8 lower eNO (14.8 ± 2.0 ppb: 3 M/5F; age: 22.0 ± 2.2 yrs) and 8 higher eNO (29.3 ± 11.6 ppb 5 M/3F; age: 22.5 ± 2.6 yrs) participants. All participants completed a control (CON) condition (no DIs pre-HFM) and DI condition (60 DI's to total lung capacity immediately pre-HFM) after an overnight fast. The primary outcome was eNO. Participants had 20 minutes to consume the HFM (1 g fat/1 kg body weight) and eNO was performed at 2- and 4- hours post-HFM. To determine whether baseline eNO levels impacted the effect of DI's, a median split was performed on their baseline eNO level.Results: There was a significant increase in eNO as a main effect of time (p < 0.001). However when analyzing the potential effect of baseline eNO, there was no significant increase in eNO post-HFM in the higher eNO group in the DI condition (p = 0.54). DIs modified the eNO response to a HFM in the group with a higher baseline eNO value.Conclusions: These data display a possible bronchoprotective protect of DIs against postprandial airway inflammation in participants with higher initial eNO level.


Assuntos
Inalação/fisiologia , Óxido Nítrico/metabolismo , Pneumonia/metabolismo , Pneumonia/fisiopatologia , Período Pós-Prandial/fisiologia , Adulto , Testes Respiratórios/métodos , Estudos Cross-Over , Feminino , Humanos , Masculino , Projetos Piloto , Sistema Respiratório/metabolismo , Sistema Respiratório/fisiopatologia , Adulto Jovem
4.
J Dairy Sci ; 103(6): 5455-5465, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32278561

RESUMO

The objectives of this study were to (1) describe the calving location of dairy cattle given access to a pasture and barn; (2) identify factors associated with calving location; and (3) compare the lying and exploratory behavior of cows in the 24 h before calving and a previous day. Seventy-two Holstein dairy heifers and cows (n = 36 nulliparous and n = 36 primiparous and multiparous combined) were housed in a covered bedded-pack barn (167.4 m2) with free access to 2.1 ha of pasture. The composition of the group was dynamic, because cows were moved in weekly at 19 ± 6 d [mean ± standard deviation (SD)] before their calving date, and were removed immediately after calving. To facilitate data collection, we divided the environment into 9 sections, including the barn (section 1; 167.4 m2), 7 sections of open pasture (sections 2 to 8; 2,402 ± 60 m2), and 1 section of pasture surrounded by natural forage cover (section 9; 3,593 m2). We then collapsed these 9 sections into 3 distinct areas for further analysis: the barn, open pasture, and natural forage cover. Animals were fitted with accelerometers to measure lying time, lying bout duration, lying bouts, and steps for the 24 h before calving (calving day) and a similar 24 h period 4 to 11 d (median = 7) before calving (baseline day). We included parity (nulliparous vs. primiparous and multiparous) and heat stress [no heat stress = temperature-humidity index (THI) ≤68 vs. heat stress = THI >68 and ≤79] in all analyses; we included time of day and group composition as additional factors that may have affected calving location. We determined exploratory behavior using 10 min instantaneous scan sampling collected from video. At each scan, we recorded the section (1 to 9) the cow or heifer was located in, and then calculated the minimum number of sections that could be crossed between successive scans. Of the total sample, 39% calved in the barn, 26% calved in the open pasture, and 35% calved in the area with natural forage cover. Nulliparous heifers and those calving when heat stress was low (THI ≤68) selected the area with natural forage cover more frequently than the barn. On the calving day, cows spent more time lying down with more short bouts of lying, and crossed more sections compared with the baseline day. Steps were affected by an interactive effect of day, parity, and heat stress; nulliparous heifers took more steps on the calving day during conditions of heat stress compared with no heat stress. Results indicate that cows and heifers had different preferences for their environment at calving, and when provided access to pasture, both changed their lying and exploratory behavior on the day of calving compared with a previous day.


Assuntos
Comportamento Animal , Bovinos/fisiologia , Comportamento Exploratório , Animais , Indústria de Laticínios , Feminino , Resposta ao Choque Térmico , Abrigo para Animais , Umidade , Lactação , Paridade , Gravidez , Temperatura
5.
Am J Transplant ; 18(8): 1924-1935, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29734498

RESUMO

The Organ Procurement and Transplantation Network monitors progress toward strategic goals such as increasing the number of transplants and improving waitlisted patient, living donor, and transplant recipient outcomes. However, a methodology for assessing system performance in providing equity in access to transplants was lacking. We present a novel approach for quantifying the degree of disparity in access to deceased donor kidney transplants among waitlisted patients and determine which factors are most associated with disparities. A Poisson rate regression model was built for each of 29 quarterly, period-prevalent cohorts (January 1, 2010-March 31, 2017; 5 years pre-kidney allocation system [KAS], 2 years post-KAS) of active kidney waiting list registrations. Inequity was quantified as the outlier-robust standard deviation (SDw ) of predicted transplant rates (log scale) among registrations, after "discounting" for intentional, policy-induced disparities (eg, pediatric priority) by holding such factors constant. The overall SDw declined by 40% after KAS implementation, suggesting substantially increased equity. Risk-adjusted, factor-specific disparities were measured with the SDw after holding all other factors constant. Disparities associated with calculated panel-reactive antibodies decreased sharply. Donor service area was the factor most associated with access disparities post-KAS. This methodology will help the transplant community evaluate tradeoffs between equity and utility-centric goals when considering new policies and help monitor equity in access as policies change.


Assuntos
Alocação de Recursos para a Atenção à Saúde/normas , Transplante de Rim/mortalidade , Alocação de Recursos/tendências , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/tendências , Listas de Espera/mortalidade , Adulto , Cadáver , Feminino , Seguimentos , Humanos , Falência Renal Crônica/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Sistema de Registros , Taxa de Sobrevida , Transplantados
6.
Eur J Neurol ; 25(6): 875-881, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29509319

RESUMO

BACKGROUND AND PURPOSE: Mutations in colony-stimulating factor 1 receptor (CSF1R) cause adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP). Patients with ALSP can be misdiagnosed as having acute ischemic stroke due to hyperintensity lesions on diffusion-weighted magnetic resonance imaging. Mutant CSF1R proteins identified in ALSP show a complete loss of autophosphorylation of CSF1R. METHODS: We conducted mutation screening of CSF1R in 123 patients with definite acute ischemic cerebrovascular syndrome and positive family history of stroke. The pathogenicity of identified variants was evaluated using functional analyses. The levels of autophosphorylation of CSF1R in response to treatment with ligands of CSF1R were examined in cells transfected with wild-type and mutant CSF1R. RESULTS: We identified eight CSF1R variants, six were known non-pathogenic polymorphisms, whereas the other two were missense variants inducing substitution of amino acid residues (p.Glu573Lys and p.Gly747Arg). Functional assay showed that the levels of autophosphorylation of p.Gly747Arg were similar to those of wild-type when treated with ligands. The autophosphorylation of p.Glu573Lys was detectable, but significantly decreased compared with those of wild-type CSF1R (P < 0.001, two-way anova with Bonferroni). The clinical presentation of the patient with p.Glu573Lys was consistent with cerebral embolism. The patient did not have typical clinical findings of ALSP. However, periventricular white matter abnormalities, unrelated to the recent infarct, were evident on brain magnetic resonance imaging. CONCLUSIONS: In contrast to ALSP-associated missense mutations, CSF1R p.Glu573Lys variant in a patient with acute ischemic cerebrovascular syndrome showed a partial loss of autophosphorylation of CSF1R; its clinical significance warrants further investigation.


Assuntos
Leucoaraiose/genética , Leucoencefalopatias/genética , Mutação de Sentido Incorreto , Receptores de Fator Estimulador de Colônias/genética , Substância Branca/patologia , Idoso , Idoso de 80 Anos ou mais , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Leucoaraiose/diagnóstico por imagem , Leucoaraiose/patologia , Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação , Receptores de Fator Estimulador de Colônias/metabolismo , Substância Branca/diagnóstico por imagem
7.
Am J Transplant ; 17 Suppl 1: 252-285, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28052602

RESUMO

Intestine and intestine-liver transplant remains important in the treatment of intestinal failure, despite decreased morbidity associated with parenteral nutrition. In 2015, 196 new patients were added to the intestine transplant waiting list, with equal numbers waiting for intestine and intestine-liver transplant. Among prevalent patients on the list at the end of 2015, 63.3% were waiting for an intestine transplant and 36.7% were waiting for an intestine-liver transplant. The pretransplant mortality rate decreased dramatically over time for all age groups. Pretransplant mortality was notably higher for intestine-liver than for intestine transplant candidates (respectively, 19.9 vs. 2.8 deaths per 100 waitlist years in 2014-2015). By age, pretransplant mortality was highest for adult candidates, at 19.6 per 100 waitlist years, and lowest for children aged younger than 6 years, at 3.6 per 100 waitlist years. Pretransplant mortality by etiology was highest for candidates with non-congenital types of short-gut syndrome. Numbers of intestine transplants without a liver increased from a low of 51 in 2013 to 70 in 2015. Intestine-liver transplants increased from a low of 44 in 2012 to 71 in 2015. Short-gut syndrome (congenital and non-congenital) was the main cause of disease leading to intestine and to intestine-liver transplant. Patient survival was lowest for adult intestine-liver recipients and highest for pediatric intestine recipients.


Assuntos
Relatórios Anuais como Assunto , Sobrevivência de Enxerto , Intestinos/transplante , Alocação de Recursos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/métodos , Humanos , Imunossupressores , Resultado do Tratamento , Estados Unidos , Listas de Espera
8.
Am J Transplant ; 17 Suppl 1: 174-251, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28052604

RESUMO

Several notable developments in adult liver transplantation in the US occurred in 2015. The year saw the largest number of liver transplants to date, leading to reductions in median waiting time, in waitlist mortality for all model for end-stage liver disease categories, and in the number of candidates on the waiting list at the end of the year. Numbers of additions to the waiting list and of liver transplants performed in patients with hepatitis C virus infection decreased for the first time in recent years. However, other diagnoses, such as non-alcoholic fatty liver disease and alcoholic cirrhosis, became more prevalent. Despite large numbers of severely ill patients undergoing liver transplant, graft survival rates continued to improve. The number of new active candidates added to the pediatric liver transplant waiting list in 2015 was 689, down from a peak of 826 in 2005. The number of prevalent pediatric candidates (on the list on December 31 of the given year) continued to decline, to 373 active and 195 inactive candidates. The number of pediatric liver transplants peaked at 613 in 2008 and was 580 in 2015. The number of living donor pediatric liver transplants increased to its highest level, 79, in 2015; most were from donors closely related to the recipients. Pediatric graft survival rates continued to improve.


Assuntos
Relatórios Anuais como Assunto , Sobrevivência de Enxerto , Transplante de Fígado , Alocação de Recursos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/métodos , Humanos , Imunossupressores , Resultado do Tratamento , Estados Unidos , Listas de Espera
9.
Am J Transplant ; 16 Suppl 2: 99-114, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26755265

RESUMO

Intestine and intestine-liver transplant plays an important role in the treatment of intestinal failure, despite decreased morbidity associated with parenteral nutrition. In 2014, 210 new patients were added to the intestine transplant waiting list. Among prevalent patients on the list at the end of 2014, 65% were waiting for an intestine transplant and 35% were waiting for an intestine-liver transplant. The pretransplant mortality rate decreased dramatically over time for all age groups. Pretransplant mortality was highest for adult candidates, at 22.1 per 100 waitlist years compared with less than 3 per 100 waitlist years for pediatric candidates, and notably higher for candidates for intestine-liver transplant than for candidates for intestine transplant without a liver. Numbers of intestine transplants without a liver increased from a low of 51 in 2013 to 67 in 2014. Intestine-liver transplants increased from a low of 44 in 2012 to 72 in 2014. Short-gut syndrome (congenital and other) was the main cause of disease leading to both intestine and intestine-liver transplant. Graft survival improved over the past decade. Patient survival was lowest for adult intestine-liver recipients and highest for pediatric intestine recipients.


Assuntos
Enteropatias/cirurgia , Intestinos/cirurgia , Intestinos/transplante , Transplante de Fígado/métodos , Transplante de Fígado/estatística & dados numéricos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto , Humanos , Imunossupressores , Masculino , Pessoa de Meia-Idade , Prevalência , Doadores de Tecidos , Resultado do Tratamento , Estados Unidos , Listas de Espera , Adulto Jovem
10.
Am J Transplant ; 16 Suppl 2: 69-98, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26755264

RESUMO

The median waiting time for patients with MELD ≥ 35 decreased from 18 days in 2012 to 9 days in 2014, after implementation of the Share 35 policy in June 2013. Similarly, mortality among candidates listed with MELD ≥ 35 decreased from 366 per 100 waitlist years in 2012 to 315 in 2014. The number of new active candidates added to the pediatric liver transplant waiting list in 2014 was 655, down from a peak of 826 in 2005. The number of prevalent candidates (on the list on December 31 of the given year) continued to decline, 401 active and 173 inactive. The number of deceased donor pediatric liver transplants peaked at 542 in 2008 and was 478 in 2014. The number of living donor liver pediatric transplants was 52 in 2014; most were from donors closely related to the recipients. Graft survival continued to improve among pediatric recipients of deceased donor and living donor livers.


Assuntos
Doença Hepática Terminal/cirurgia , Transplante de Fígado/métodos , Transplante de Fígado/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Doença Hepática Terminal/epidemiologia , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Doadores Vivos , Pessoa de Meia-Idade , Fatores de Tempo , Doadores de Tecidos , Resultado do Tratamento , Estados Unidos , Listas de Espera , Adulto Jovem
11.
Nature ; 465(7298): 590-3, 2010 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-20520708

RESUMO

A network is frustrated when competing interactions between nodes prevent each bond from being satisfied. This compromise is central to the behaviour of many complex systems, from social and neural networks to protein folding and magnetism. Frustrated networks have highly degenerate ground states, with excess entropy and disorder even at zero temperature. In the case of quantum networks, frustration can lead to massively entangled ground states, underpinning exotic materials such as quantum spin liquids and spin glasses. Here we realize a quantum simulation of frustrated Ising spins in a system of three trapped atomic ions, whose interactions are precisely controlled using optical forces. We study the ground state of this system as it adiabatically evolves from a transverse polarized state, and observe that frustration induces extra degeneracy. We also measure the entanglement in the system, finding a link between frustration and ground-state entanglement. This experimental system can be scaled to simulate larger numbers of spins, the ground states of which (for frustrated interactions) cannot be simulated on a classical computer.

12.
Am J Transplant ; 15 Suppl 2: 1-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25626347

RESUMO

Despite improvements in medical and surgical treatment of intestinal failure over the past decade, intestine transplant continues to play an important role. Of 171 new patients added to the intestine transplant waiting list in 2013, 49% were listed for intestine-liver transplant and 51% for intestine transplant alone or with an organ other than liver. The pretransplant mortality rate decreased dramatically over time for all age groups, from 30.3 per 100 waitlist years in 2002-2003 to 6.9 for patients listed in 2012-2013. The number of intestine transplants decreased from 91 in 2009 to 51 in 2013; intestine-liver transplants decreased from 135 in 2007 to a low of 44 in 2012, but increased slightly to 58 in 2013. Ages of intestine and intestineliver transplant recipients have changed substantially; the number of adult recipients was double the number of pediatric recipients in 2013. Graft survival improved over the past decade. Graft failure in the first 90 days posttransplant occurred in 14.1% of intestine recipients and in 11.2% of intestine-liver recipients in 2013. The number of recipients alive with a functioning intestine graft has steadily increased since 2002, to 1012 in 2013; almost half were pediatric intestine-liver transplant recipients.


Assuntos
Relatórios Anuais como Assunto , Enteropatias/cirurgia , Intestinos/transplante , Doadores de Tecidos , Listas de Espera , Adolescente , Adulto , Criança , Feminino , Sobrevivência de Enxerto , Humanos , Enteropatias/mortalidade , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Transplante de Órgãos/estatística & dados numéricos , Readmissão do Paciente , Alocação de Recursos , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos , Adulto Jovem
13.
Am J Transplant ; 15 Suppl 2: 1-28, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25626341

RESUMO

During 2013, 10,479 adult candidates were added to the liver transplant waiting list, compared with 10,185 in 2012; 5921 liver transplants were performed, and 211 of the transplanted organs were from living donors. As of December 31, 2013, 15,027 candidates were registered on the waiting list, including 12,407 in active status. The most significant change in allocation policy affecting liver waitlist trends in 2013 was the Share 35 policy, whereby organs from an entire region are available to candidates with model for end-stage liver disease scores of 35 or higher. Median waiting time for such candidates decreased dramatically, from 14.0 months in 2012 to 1.4 months in 2013, but the effect on waitlist mortality is unknown. The number of new active pediatric candidates added to the liver transplant waiting list increased to 693 in 2013. Transplant rates were highest for candidates aged younger than 1 year (275.6 per 100 waitlist years) and lowest for candidates aged 11 to 17 years (97.0 per 100 waitlist years). Five-year graft survival was 71.7% for recipients aged younger than 1 year, 74.9% for ages 1 to 5 years, 78.9% ages 6 to 10 years, and 77.4% for ages 11 to 17 years.


Assuntos
Relatórios Anuais como Assunto , Hepatopatias/cirurgia , Transplante de Fígado/estatística & dados numéricos , Alocação de Recursos , Doadores de Tecidos , Listas de Espera , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto , Humanos , Lactente , Recém-Nascido , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos , Adulto Jovem
14.
Biol Lett ; 11(7)2015 07.
Artigo em Inglês | MEDLINE | ID: mdl-26156132

RESUMO

The foraging strategy of many animals is thought to be determined by their past experiences. However, few empirical studies have investigated whether this is true in diving animals. We recorded three-dimensional movements and mouth-opening events from three Antarctic fur seals during their foraging trips to examine how they adapt their behaviour based on past experience--continuing to search for prey in the same area or moving to search in a different place. Each dive cycle was divided into a transit phase and a feeding phase. The linear horizontal distance travelled after feeding phases in each dive was affected by the mouth-opening rate during the previous 244 s, which typically covered two to three dive cycles. The linear distance travelled tended to be shorter when the mouth-opening rate in the previous 244 s was higher, i.e. seals tended to stay in the same areas with high prey-encounter rates. These results indicate that Antarctic fur seals follow decision-making strategies based on the past foraging experience over time periods longer than the immediately preceding dive.


Assuntos
Mergulho/fisiologia , Comportamento Alimentar/fisiologia , Otárias/fisiologia , Comportamento Predatório/fisiologia , Animais , Regiões Antárticas , Feminino , Fatores de Tempo
15.
Am J Transplant ; 14 Suppl 1: 97-111, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24373169

RESUMO

Advances in the medical and surgical treatments of intestinal failure have led to a decrease in the number of transplants over the past decade. In 2012, 152 candidates were added to the intestinal transplant waiting list, a new low. Of these, 64 were listed for intestine-liver transplant and 88 for intestinal transplant alone or with an organ other than liver. Historically, the most common organ transplanted with the intestine was the liver; this practice decreased substantially from a peak of 52.9% in 2007 to 30.0% in 2012. Short-gut syndrome, which encompasses a large group of diagnoses, is the most common etiology of intestinal failure. The pretransplant mortality rate decreased dramatically over time for all age groups, from 51.0 per 100 wait-list years in 1998-1999 to 6.7 for patients listed in 2010-2012. Numbers of intestinal and intestine-liver transplants steadily decreased from 198 in 2007 to 106 in 2012. By age, intestinal transplant recipients have changed substantially; the number of adult recipients now approximately equals the number of pediatric recipients. Graft survival has improved over the past decade. Graft failure in the first 90 days after transplant occurred in 15.7% of 2011-2012 intestinal transplant recipients, compared with 21% in 2001-2002.


Assuntos
Intestinos/transplante , Adolescente , Adulto , Criança , Pré-Escolar , Sobrevivência de Enxerto , Humanos , Intestinos/cirurgia , Transplante de Fígado , Readmissão do Paciente , Síndrome do Intestino Curto/cirurgia , Resultado do Tratamento , Listas de Espera/mortalidade
16.
Am J Transplant ; 14(6): 1310-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24786673

RESUMO

In response to recommendations from a recent consensus conference and from the Committee of Presidents of Statistical Societies, the Scientific Registry of Transplant Recipients explored the use of Bayesian hierarchical, mixed-effects models in assessing transplant program performance in the United States. Identification of underperforming centers based on 1-year patient and graft survival using a Bayesian approach was compared with current observed-to-expected methods. Fewer small-volume programs (<10 transplants per 2.5-year period) were identified as underperforming with the Bayesian method than with the current method, and more mid-volume programs (10-249 transplants per 2.5-year period) were identified. Simulation studies identified optimal Bayesian-based flagging thresholds that maximize true positives while holding false positive flagging rates to approximately 5% regardless of program volume. Compared against previous program surveillance actions from the Organ Procurement and Transplantation Network Membership and Professional Standards Committee, the Bayesian method would have reduced the number of false positive program identifications by 50% for kidney, 35% for liver, 43% for heart and 57% for lung programs, while preserving true positives for, respectively, 96%, 71%, 58% and 83% of programs identified by the current method. We conclude that Bayesian methods to identify underperformance improve identification of programs that need review while minimizing false flags.


Assuntos
Sistema de Registros , Transplante , Algoritmos , Humanos
17.
Am J Transplant ; 14 Suppl 1: 69-96, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24373168

RESUMO

Liver transplant in the us remains a successful life-saving procedure for patients with irreversible liver disease. In 2012, 6256 adult liver transplants were performed, and more than 65,000 people were living with a transplanted liver. The number of adults who registered on the liver transplant waiting list decreased for the first time since 2002; 10,143 candidates were added, compared with 10,359 in 2011. However, the median waiting time for active wait-listed adult candidates increased, as did the number of candidates removed from the list because they were too sick to undergo transplant. The overall deceased donor transplant rate decreased to 42.3 per 100 patient-years, and varied geographically from 18.9 to 228.0 per 100 patient-years. Graft survival continues to improve, especially for donation after circulatory death livers. The number of new active pediatric candidates added to the waiting list also decreased. Almost 75% of pediatric candidates listed in 2009 underwent transplant within 3 years; the 2012 rate of deceased donor transplants among active pediatric wait-listed candidates was 136 per 100 patient-years. Graft survival for deceased donor pediatric transplants was 92.8% at 30 days. Medicare paid for some or all of the care for more than 30% of liver transplants in 2010.


Assuntos
Transplante de Fígado , Adulto , Criança , Infecções por Citomegalovirus/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Rejeição de Enxerto , Antígenos do Núcleo do Vírus da Hepatite B/análise , Antígenos de Superfície da Hepatite B/análise , Hepatite C/imunologia , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/economia , Doadores Vivos , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Resultado do Tratamento , Estados Unidos/epidemiologia , Listas de Espera/mortalidade
18.
Opt Lett ; 39(11): 3238-41, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24876022

RESUMO

We stabilize a chosen radio frequency beat note between two optical fields derived from the same mode-locked laser pulse train in order to coherently manipulate quantum information. This scheme does not require access or active stabilization of the laser repetition rate. We implement and characterize this external lock, in the context of two-photon stimulated Raman transitions between the hyperfine ground states of trapped 171Yb(+) quantum bits.

19.
Phys Rev Lett ; 113(22): 227401, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25494089

RESUMO

Terahertz near fields of gold metamaterials resonant at a frequency of 0.88 THz allow us to enter an extreme limit of nonperturbative ultrafast terahertz electronics: Fields reaching a ponderomotive energy in the keV range are exploited to drive nondestructive, quasistatic interband tunneling and impact ionization in undoped bulk GaAs, injecting electron-hole plasmas with densities in excess of 10^{19} cm^{-3}. This process causes bright luminescence at energies up to 0.5 eV above the band gap and induces a complete switch-off of the metamaterial resonance accompanied by self-amplitude-modulation of transmitted few-cycle terahertz transients. Our results pave the way towards highly nonlinear terahertz optics and optoelectronic nanocircuitry with subpicosecond switching times.

20.
Mar Pollut Bull ; 198: 115891, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38101054

RESUMO

As awareness on the impact of anthropogenic underwater noise on marine life grows, underwater noise measurement programs are needed to determine the current status of marine areas and monitor long-term trends. The Joint Monitoring Programme for Ambient Noise in the North Sea (JOMOPANS) collaborative project was funded by the EU Interreg to collect a unique dataset of underwater noise levels at 19 sites across the North Sea, spanning many different countries and covering the period from 2019 to 2020. The ambient noise from this dataset has been characterised and compared - setting a benchmark for future measurements in the North Sea area. By identifying clusters with similar sound characteristics in three broadband frequency bands (25-160 Hz, 0.2-1.6 kHz, and 2-10 kHz), geographical areas that are similarly affected by sound have been identified. The measured underwater sound levels show a persistent and spatially uniform correlation with wind speed at high frequencies (above 1 kHz) and a correlation with the distance from ships at mid and high frequencies (between 40 Hz and 4 kHz). Correlation with ocean current velocity at low frequencies (up to 200 Hz), which are susceptible to nonacoustic contamination by flow noise, was also evaluated. These correlations were evaluated and simplified linear scaling laws for wind and current speeds were derived. The presented dataset provides a baseline for underwater noise measurements in the North Sea and shows that spatial variability of the dominant sound sources must be considered to predict the impact of noise reduction measures.


Assuntos
Acústica , Som , Mar do Norte , Ruído , Meio Ambiente , Navios
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