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1.
Tech Coloproctol ; 27(12): 1227-1234, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36973527

RESUMO

PURPOSE: In patients with chemotherapy, there is no consensus on the timing of ileostomy closure. Ileostomy reversal could improve the quality of life and minimise the long-term adverse events of delayed closure. In this study, we evaluated the impact of chemotherapy on ileostomy closure and searched for the predictive factors for complications. METHODS: We retrospectively analysed 212 patients with rectal cancer who underwent ileostomy closure surgery during and without chemotherapy and were consecutively enrolled between 2010 and 2016. As a result of the heterogeneity of the two groups, propensity score matching (PSM) was performed with a 1:1 PSM cohort. RESULTS: A total of 162 patients were included in the analysis. The overall stoma closure-related complications (12.4% vs. 11.1%, p = 1.00) and major complications (2.5% vs. 6.2%, p = 0.44) were not significantly different between the two groups. Multivariate analysis demonstrated that chronic kidney disease and bevacizumab use are risk factors for major complications. CONCLUSION: Patients with oral or intravenous chemotherapy can safely have ileostomy closure with an adequate time delay from chemotherapy. When patients use bevacizumab, major complications related to ileostomy closure should still be cautioned.


Assuntos
Ileostomia , Neoplasias Retais , Humanos , Ileostomia/efeitos adversos , Estudos Retrospectivos , Bevacizumab/uso terapêutico , Pontuação de Propensão , Qualidade de Vida , Complicações Pós-Operatórias/etiologia , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/cirurgia , Neoplasias Retais/complicações , Resultado do Tratamento
2.
Zhonghua Yan Ke Za Zhi ; 58(11): 882-889, 2022 Nov 11.
Artigo em Zh | MEDLINE | ID: mdl-36348524

RESUMO

Objective: To report the incidence and time distribution of early transient intraocular pressure (IOP) elevation after penetrating canaloplasty. Methods: Retrospective case series study. Data of patients treated by penetrating canaloplasty for glaucoma in the Eye Hospital of Wenzhou Medical University from June 2015 to March 2020 were collected. Early transient IOP elevation was defined as an increase of IOP to over 21 mmHg on the first week to the third month after surgery followed by a decrease to 21 mmHg or less within 3 months. Main outcome measures included IOP, quantity of medication use, the occurrence time and duration of IOP elevation. Generalized estimating equations were used for statistical analysis, and measurement data with non-normal distribution was represented as M (Q1, Q3). Results: A total of 277 patients (315 eyes) achieved 360-degree catheterization of the canal successfully, and 299 eyes (94.9%) completed the postoperative 6-month follow-up. Thirty-four eyes (10.8%) had persistently high IOP, so the surgical treatment failed in them. Consequently, 234 patients (265 eyes) were enrolled in the analyses, including 161 males (184 eyes) and 73 females (81 eyes). The median age was 42 (26, 54) years, the mean preoperative IOP was (37.7±11.1) mmHg, and the mean number of drugs used was 3 (2, 4). The incidence of early transient IOP elevation was 43.0% (114/265) in all enrolled eyes, 42.7% (35/82) in eyes with primary open angle glaucoma, 37.8% (17/45) in eyes with primary angle closure glaucoma, 27.7% (13/47) in eyes with congenital glaucoma and 53.8% (49/91) in eyes with secondary glaucoma. The IOP began to increase on the first to fourth week in 91.2% (104/114) of eyes with early transient IOP elevation and reached the peak [21.3 mmHg to 54.8 mmHg; mean, (32.4±8.2) mmHg] in 88.6% (101/114) on the first to fifth week after surgery. The IOP elevation lasted for no more than 4 weeks in 69.3% (79/114) of eyes. Conclusions: Over 40.0% of patients with penetrating canaloplasty may experience postoperative transient IOP elevation. The incidence is relatively high in secondary glaucoma but low in congenital glaucoma. Most of the elevations and peak IOP occur within 1-4 weeks after surgery.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Masculino , Feminino , Humanos , Adulto , Pressão Intraocular , Glaucoma de Ângulo Aberto/cirurgia , Estudos Retrospectivos , Incidência , Glaucoma/cirurgia , Resultado do Tratamento
3.
Opt Lett ; 46(15): 3604-3607, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329235

RESUMO

Temperature-dependent characteristics of GeSn/Ge multiple-quantum-well (MQW) photoconductors (PCs) on silicon substrate were investigated. The high quality GeSn/Ge MQW epitaxial structure was grown on a silicon substrate using low temperature molecular beam epitaxy techniques with atomically precise thickness control. Surface-illuminated GeSn/Ge MQW PCs were fabricated using complementary metal-oxide-semiconductor-compatible processing and characterized in a wide temperature range of 55-320 K. The photodetection range was extended to λ=2235nm at T=320K due to bandgap shrinkage with Sn alloying. Measured spectral responsivity was enhanced at reduced temperatures. These results provide better understanding of GeSn/Ge MQW structures for efficient short-wave infrared photodetection.

4.
Opt Lett ; 46(13): 3316-3319, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34197445

RESUMO

We report normal-incidence planar GeSn resonant-cavity-enhanced photodetectors (RCE-PDs) with a lateral p-i-n homojunction configuration on a silicon-on-insulator (SOI) platform for short-wave infrared (SWIR) integrated photonics. The buried oxide of the SOI platform and the deposited SiO2 layer serve as the bottom and top reflectors, respectively, creating a vertical cavity for enhancing the optical responsivity. The planar p-i-n diode structure is favorable for complementary-metal-oxide-semiconductor-compatible, large-scale integration. With the bandgap reduction enabled by the 4.2% Sn incorporation into the GeSn active layer, the photodetection range extends to 1960 nm. The promising results demonstrate that the developed planar GeSn RCE-PDs are potential candidates for SWIR integrated photonics.

5.
Opt Lett ; 46(4): 864-867, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33577533

RESUMO

In this Letter, we demonstrate mid-infrared (MIR) lateral p-i-n GeSn waveguide photodetectors (WGPDs) on silicon, to the best of our knowledge for the first time, as a key enabler of MIR electronic-photonic integrated circuits (EPICs). Narrow-bandgap GeSn alloys were employed as the active material to enable efficient photodetection in the MIR region. A lateral p-i-n homojunction diode was designed and fabricated to significantly enhance the optical confinement factor of the guided modes and thus enhance the optical responsivity. Thus, a photodetection range of up to 1950 nm and a good responsivity of 0.292 A/W at 1800 nm were achieved. These results demonstrate the feasibility of planar GeSn WGPDs for monolithic MIR EPICs on silicon.

6.
Nanotechnology ; 32(35)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34020429

RESUMO

The application of strain into GeSn alloys can effectively modulate the band structures, thus creating novel electronic and photonic devices. Raman spectroscopy is a powerful tool for characterizing strain; however, the lack of Raman coefficient makes it difficult for accurate determination of strain in GeSn alloys. Here, we have investigated the Raman-strain function of Ge1-xSnxalong 〈1 0 0〉 and 〈1 1 0〉 directions. GeSn nanomembranes (NMs) with different Sn compositions are transfer-printed on polyethylene terephthalate substrates. External strain is introduced by bending fixtures with different radii, leading to uniaxial tensile strain up to 0.44%. Strain analysis of flexible GeSn NMs bent along 〈1 0 0〉 and 〈1 1 0〉 directions are performed by Raman spectroscopy. The linear coefficients of Raman-strain for Ge0.96Sn0.04are measured to be -1.81 and -2.60 cm-1, while those of Ge0.94Sn0.06are decreased to be -2.69 and -3.82 cm-1along 〈1 0 0〉 and 〈1 1 0〉 directions, respectively. As a result, the experimental ratio of linear coefficient (ROLC) of Ge, Ge0.96Sn0.04and Ge0.94Sn0.06are 1.34, 1.44 and 1.42, which agree well with theoretical ROLC values calculated by elastic compliances and phonon deformation potentials (PDPs). In addition, the compositional dependence of PDPs is analyzed qualitatively. These fundamental parameters are important in designing high performance strained GeSn electronic and photonic devices.

7.
Opt Lett ; 45(5): 1088-1091, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32108777

RESUMO

We demonstrate silicon-based $p \text{-} n \text{-} p$p-n-p floating-base GeSn heterojunction phototransistors with enhanced optical responsivity for efficient short-wave infrared (SWIR) photodetection. The narrow-bandgap GeSn active layer sandwiched between the $p \text{-} {\rm Ge}$p-Ge collector and $n \text{-} {\rm Ge}$n-Ge base effectively extends the photodetection range in the SWIR range, and the internal gain amplifies the optical response by a factor of more than three at a low driving voltage of 0.4 V compared to that of a reference GeSn $p \text{-} i \text{-} n$p-i-n photodetector (PD). We anticipate that our findings will be leveraged to realize complementary metal-oxide-semiconductor-compatible, sensitive, low driving voltage SWIR PDs in a wide range of applications.

8.
Opt Lett ; 45(6): 1463-1466, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32163992

RESUMO

The 2 µm wavelength band has recently gained increased attention for potential applications in next-generation optical communication. However, it is still challenging to achieve effective photodetection in the 2 µm wavelength band using group-IV-based semiconductors. Here we present an investigation of GeSn resonant-cavity-enhanced photodetectors (RCEPDs) on silicon-on-insulator substrates for efficient photodetection in the 2 µm wavelength band. Narrow-bandgap GeSn alloys are used as the active layer to extend the photodetection range to cover the 2 µm wavelength band, and the optical responsivity is significantly enhanced by the resonant cavity effect as compared to a reference GeSn photodetector. Temperature-dependent experiments demonstrate that the GeSn RCEPDs can have a wider photodetection range and higher responsivity in the 2 µm wavelength band at higher temperatures because of the bandgap shrinkage. These results suggest that our GeSn RCEPDs are promising for complementary metal-oxide-semiconductor-compatible, efficient, uncooled optical receivers in the 2 µm wavelength band for a wide range of applications.

9.
Zhonghua Yan Ke Za Zhi ; 55(10): 777-784, 2019 Oct 11.
Artigo em Zh | MEDLINE | ID: mdl-31607067

RESUMO

Objective: To evaluate risk factors for visual field (VF) loss progression in primary open-angle glaucoma patients. Methods: A prospective nested case-control study. Patients were collected from the Wenzhou glaucoma progression study in the Eye Hospital of Wenzhou Medical University during March 2014 and April 2018. In this study, the eyes were divided into a progression group and a non-progression group using the glaucoma progression analysis methods to analyze the risk factors for glaucomatous VF loss progression. Axial length (AL) and central corneal thickness (CCT) were measured using the Lenstar LS900. The baseline, fluctuation (standard deviation), mean, maximum, minimum and range of intraocular pressure (IOP) during the follow-up period were determined based on IOP measured at each follow-up. The IOP measurements were included from the baseline to the last visit (for the non-progression group), or to the visit at which VF loss progression was determined (for the progression group). The independent sample t-test, Mann-Whitney U inspection and Cox proportional hazards models were used for statistical analysis. Results: A total of 140 patients (140 eyes) were enrolled, including 67 males and 73 females. There were 19.3% of the eyes (27 of 140 eyes) showing VF loss progression. The median time to the endpoint for progression was 24.0 (16.0, 40.0) months. The AL in the progression group and non-progression group were 23.58 (23.05, 24.24) mm and 23.91 (23.10, 24.91) mm (P=0.111). The CCT in the two groups were 531.0 (512.0, 565.0) µm and 535.0 (518.5, 552.0) µm, respectively (P=0.897). The baseline age in the progression group and non-progression group was 71.0 (68.0, 74.0) years and 68.0 (58.0, 72.0) years, respectively (Z=-2.872, P=0.004). The slope of visual field index in the two groups was -3.50 (-7.10, -1.80)%/year and 0.40 (-0.60, 1.40)%/year, respectively (Z=-6.823, P<0.01). The mean IOP during the follow-up was (16.2±2.7) mmHg (1 mmHg=0.133 kPa) in the progression group and (15.1±2.4) mmHg in the non-progression group (t=-2.215, P=0.028). The IOP fluctuation in the progression group and non-progression group was (2.6±1.3) mmHg and (2.0±0.7) mmHg, respectively (t=-2.175, P=0.038). In the multivariate model, older baseline age (HR=1.080; 95%CI:1.019-1.143), higher baseline IOP (HR=1.120; 95%CI:1.016-1.236), higher mean IOP (HR=1.145; 95%CI:1.001-1.309) and higher IOP fluctuation (HR=1.750; 95%CI:1.193-2.566) were all significantly predictive risk factors for glaucomatous VF loss progression. Longer AL (HR=0.725; 95%CI:0.532-0.988) was a protective factor against VF loss progression. However, CCT was found to be not associated with VF loss progression. Conclusion: Baseline age, baseline IOP, mean IOP, IOP fluctuation and shorter AL are found to be risk factors for glaucomatous VF loss progression among eyes with primary open-angle glaucoma in Wenzhou. (Chin J Ophthalmol, 2019, 55: 777-784).


Assuntos
Córnea/anatomia & histologia , Glaucoma de Ângulo Aberto/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Transtornos da Visão/fisiopatologia , Campos Visuais , Idoso , Estudos de Casos e Controles , Paquimetria Corneana , Progressão da Doença , Feminino , Glaucoma de Ângulo Aberto/diagnóstico , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Testes de Campo Visual
10.
Zhonghua Yan Ke Za Zhi ; 55(6): 448-453, 2019 Jun 11.
Artigo em Zh | MEDLINE | ID: mdl-31189275

RESUMO

Objective: To evaluate the preliminary efficacy and safety of penetrating canaloplasty for treating primary angle-closure glaucoma (PACG). Methods: It is a prospective interventional case series study. Twenty-two patients (24 eyes) with PACG were treated with penetrating canaloplasty (video attached) at the Eye Hospital of Wenzhou Medical University from June 2015 to August 2018. This modified canaloplasty was performed by making a window at the corneal-scleral bed. Aqueous was redirected to the opening of Schlemm's canal after the canaloplasty with intension sutures. Postoperative follow-up was made at 1 day, 7 days, 1 month, 3 months, and 6 months. Surgical success was defined as intraocular pressure (IOP) ≤ 21 mmHg (1 mmHg=0.133 kPa) with glaucoma medication (quantified success) and without any glaucoma medication (complete success). Main outcome measures included IOP, number of medication, surgical success rate, complications, and filtering bleb status. One-way repeated measure ANOVA and rank sum test were used in statistical analysis. Results: Due to the failure of circumferential catheterization of the canal, 4 eyes converted to trabeculectomy. A total of 19 PACG patients (20 eyes) achieved the successful 360-degree catheterization of the canal, including 11 males and 8 females. The mean age was (54±7) years old (range: 41-65 years old), and the mean angle-closure range was (326.3±46.6) degrees. The mean preoperative IOP was (38.0±11.9) mmHg with the median medication number of 3 (range: 2-5). The mean postoperative IOP was (14.5±11.1), (16.1±6.0), (17.7±5.5), (15.7±5.0), and (15.4±3.7) mmHg at 1 day, 7 days, 1 month, 3 months, and 6 months, respectively. There was significant difference in IOP between postoperative and preoperative (all P<0.01). The median medication number (range) was 0 (0-3), 0 (0-2), 0(0-3), 0(0-2), and 0 (0-2) at the 5 time points, respectively. There was significant difference in medication number between postoperative and preoperative (all P<0.01). The quantified success rate was 95%(19/20), and the complete success rate was 90%(18/20) at 6 months. Postoperative complications were observed in 7 eyes (35%) of 20 PACG eyes, including 3 eyes (15%) with hyphema, 2 eyes (10%) with shallow anterior chamber, 1 eye (5%) with Descemet membrane detachment, and 1 eye (5%) with filtration obstruction at the trabeculum ostium. According to the results of slit lamp and ultrasound biomicroscopy examinations, 70% of the eyes (14/20) had no filtering bleb. Eight eyes (40%) with IOP spike were observed. Conclusion: Preliminary study shows penetrating canaloplasty is safe and effective in the treatment of PACG, but needs a longer follow-up. (Chin J Ophthalmol, 2019, 55: 448-453).


Assuntos
Glaucoma de Ângulo Fechado , Glaucoma de Ângulo Aberto , Trabeculectomia , Adulto , Idoso , Feminino , Glaucoma de Ângulo Fechado/cirurgia , Glaucoma de Ângulo Aberto/cirurgia , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acuidade Visual
11.
Opt Lett ; 43(6): 1215-1218, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29543254

RESUMO

We report GeSn p-i-n resonant-cavity-enhanced photodetectors (RCEPDs) grown on silicon-on-insulator substrates. A vertical cavity, composed of a buried oxide as the bottom reflector and a deposited SiO2 layer on the top surface as the top reflector, is created for the GeSn p-i-n structure to enhance the light-matter interaction. The responsivity experiments demonstrate that the photodetection range is extended to 1820 nm, completely covering all the telecommunication bands, because of the introduction of 2.5% Sn in the photon-absorbing layer. In addition, the responsivity is significantly enhanced by the resonant cavity effects, and a responsivity of 0.376 A/W in the telecommunication C-band is achieved that is significantly higher than that of conventional GeSn-based PDs. These results demonstrate the feasibility of CMOS-compatible, high-responsivity GeSn-based PDs for shortwave infrared applications.

12.
Opt Lett ; 42(9): 1652-1655, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28454127

RESUMO

We report on Sn-based p-i-n waveguide photodetectors (WGPD) with a pseudomorphic GeSn/Ge multiple-quantum-well (MQW) active layer on a Ge-buffered Si substrate. A reduced dark-current density of 59 mA/cm2 was obtained at a reverse bias of 1 V due to the suppressed strain relaxation in the GeSn/Ge active layer. Responsivity experiments revealed an extended photodetection range covering the O, E, S, C, and L telecommunication bands completely due to the bandgap reduction resulting from Sn-alloying. Band structure analysis of the pseudomorphic GeSn/Ge quantum well structures indicated that, despite the stronger quantum confinement, the absorption edge can be shifted to longer wavelengths by increasing the Sn content, thereby enabling efficient photodetection in the infrared region. These results demonstrate the feasibility of using GeSn/Ge MQW planar photodetectors as building blocks of electronic-photonic integrated circuits for telecommunication and optical interconnection applications.

13.
Opt Express ; 24(16): 17562-71, 2016 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-27505727

RESUMO

We report on tensile-strained Ge/Si0.11Ge0.89 quantum-well (QW) metal-semiconductor-metal (MSM) photodetectors on Si substrates. A tensile strain of 0.21% is introduced into the Ge wells by growing the QW stack on in-situ annealed Ge-on-Si virtual substrates (VS). The optical characterization of Ge/Si0.11Ge0.89 QW MSM photodetectors indicates that the optical response increases to a wavelength of 1.5 µm or higher owing to the strain-induced direct bandgap shrinkage. Analysis of the band structure by using a k · p model suggests that by optimizing the tensile strain and Ge well width, tensile-strained Ge/SiGe QW photodetectors can be designed to cover the telecommunication C-band and beyond for optical telecommunications and on-chip interconnection.

15.
Eur Rev Med Pharmacol Sci ; 28(5): 1639, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38497847

RESUMO

The article "MiR-221 inhibits proliferation of pancreatic cancer cells via down regulation of SOCS3", by J. Xie, J.-T. Wen, X.-J. Xue, K.-P. Zhang, X.-Z. Wang, H.-H. Cheng, published in Eur Rev Med Pharmacol Sci 2018; 22 (7): 1914-1921-DOI: 10.26355/eurrev_201804_14714-PMID: 29687843 has been retracted by the Editor in Chief for misconduct and data fabrication. An investigation conducted by the National Health Commission of the People's Republic of China, determined that the information and images presented in the paper have been manipulated, pieced together, and subjected to various fraudulent alterations. Consequently, the Editor in Chief mistrusts the results presented and has decided to withdraw the articles. The corresponding authors did not respond to journal correspondence about the investigation and retraction of this article. This article has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/14714.

16.
Opt Express ; 20(18): 19905-11, 2012 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23037042

RESUMO

We report here the first demonstration of a harmonic mode-locked Raman fiber laser using the intermodal beating of a continuous-wave (CW) multiple-longitudinal-mode pump laser. By matching the Raman-cavity round-trip frequency with the intermodal-beating one of a 1064 nm CW pump source, harmonic mode-locking in phosphosilicate Raman fiber laser is stably initiated at the first-order Stokes of 1239.5 nm, and generates rectangular-shape nanosecond pulses with the pulse energy up to 4.25 nJ. Using the new type of mode-locking, the harmonic order can be discretely tuned from 78 th- to 693 rd-order, and the cavity supermode is suppressed up to 51.1 dB with the signal-to-noise ratio of more than 65 dB.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Lasers de Estado Sólido , Análise Espectral Raman/instrumentação , Telecomunicações/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
17.
Cytogenet Genome Res ; 134(1): 19-26, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21335957

RESUMO

The first build of the chicken genome sequence appeared in March, 2004 - the first genome sequence of any animal agriculture species. That sequence was done primarily by whole genome shotgun Sanger sequencing, along with the use of an extensive BAC contig-based physical map to assemble the sequence contigs and scaffolds and align them to the known chicken chromosomes and linkage groups. Subsequent sequencing and mapping efforts have improved upon that first build, and efforts continue in search of missing and/or unassembled sequence, primarily on the smaller microchromosomes and the sex chromosomes. In the past year, a draft turkey genome sequence of similar quality has been obtained at a much lower cost primarily due to the development of 'next-generation' sequencing techniques. However, assembly and alignment of the sequence contigs and scaffolds still depended on a detailed BAC contig map of the turkey genome that also utilized comparison to the existing chicken sequence. These 2 land fowl (Galliformes) genomes show a remarkable level of similarity, despite an estimated 30-40 million years of separate evolution since their last common ancestor. Among the advantages offered by these sequences are routine re-sequencing of commercial and research lines to identify the genetic correlates of phenotypic change (for example, selective sweeps), a much improved understanding of poultry diversity and linkage disequilibrium, and access to high-density SNP typing and association analysis, detailed transcriptomic and proteomic studies, and the use of genome-wide marker- assisted selection to enhance genetic gain in commercial stocks.


Assuntos
Genoma , Aves Domésticas/genética , Animais , Sequência de Bases , Evolução Molecular , Ligação Genética , Técnicas Genéticas , Humanos
19.
Poult Sci ; 90(6): 1206-11, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21597060

RESUMO

Marek's disease (MD) is a T cell lymphoma disease of domestic chickens induced by the Marek's disease virus (MDV), a highly infectious and naturally oncogenic alphaherpesvirus. Enhancing genetic resistance to MD in poultry is an attractive method to augment MD vaccines, which protect against MD but do not prevent MDV replication and horizontal spread. Previous work integrating QTL scans, transcript profiling, and MDV-chicken protein-protein interaction screens revealed 3 MD resistance genes; however, a major challenge continues to be the identification of the other contributing genes. To aid in this search, we screened for allele-specific expression (ASE) in response to MDV infection, a simple and novel method for identifying polymorphic cis-acting regulatory elements, which may contain strong candidate genes with specific alleles that confer MD genetic resistance. In this initial study, we focused on immunoglobulin ß (CD79B) because it plays a critical role in the immune response and, more important, is transcriptionally coupled with growth hormone (GH1), one of the previously identified MD resistance genes. Using a coding SNP in CD79B and pyrosequencing to track the relative expression of each allele, we monitored ASE in uninfected and MDV-infected F(1) progeny from reciprocal intermatings of highly inbred chicken lines 6(3) (MD resistant) and 7(2) (MD susceptible). Upon screening 3 tissues (bursa, thymus, and spleen) at 5 time points (1, 4, 7, 11, and 15 d postinfection), we observed that MDV infection alters the CD79B allelic ratios in bursa and thymus tissues at 4 and 15 d postinfection in both mating directions. Our results suggest that CD79B has a cis-acting regulatory element that responds to MDV infection and probably cooperates with GH1 in conferring genetic resistance to MD. This result helps validates the use of ASE screens to identify specific candidate genes for complex traits such as genetic resistance to MD.


Assuntos
Antígenos CD79/genética , Galinhas/genética , Regulação da Expressão Gênica/imunologia , Doença de Marek/genética , Elementos Reguladores de Transcrição/genética , Alelos , Animais , Antígenos CD79/imunologia , Predisposição Genética para Doença , Testes Genéticos , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo
20.
Opt Express ; 18(19): 19957-65, 2010 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-20940887

RESUMO

This paper presents modeling and simulation of a silicon-based group IV semiconductor injection laser diode in which the active region has a multiple quantum well structure formed with Ge(0.9)Sn(0.1) quantum wells separated by Ge(0.75)Si(0.1)Sn(0.15) barriers. These alloy compositions were chosen to satisfy three conditions simultaneously: a direct band gap for Ge(0.9)Sn(0.1), type-I band alignment between Ge(0.9)Sn(0.1) and Ge(0.75)Si(0.1)Sn(0.15,) and a lattice match between wells and barriers. This match ensures that the entire structure can be grown strain free upon a relaxed Ge(0.75)Si(0.1)Sn(0.15) buffer on a silicon substrate - a CMOS compatible process. Detailed analysis is performed for the type I band offsets, carrier lifetime, optical confinement, and modal gain. The carrier lifetime is found to be dominated by the spontaneous radiative process rather than the Auger process. The modal gain has a rather sensitive dependence on the number of quantum wells in the active region. The proposed laser is predicted to operate at 2.3 µm in the mid infrared at room temperature.


Assuntos
Lasers Semicondutores , Silício/química , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Raios Infravermelhos , Temperatura
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