Publications by authors named "Jason Mckinney"

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  • Extrapulmonary small cell carcinoma (EPSCC) is a rare type of cancer that has unique clinical and pathological traits.
  • A 72-year-old male was found to have EPSCC in his rectum during a routine colonoscopy, despite showing no symptoms.
  • The treatment administered involved radiation therapy along with chemotherapy using cisplatin and etoposide, highlighting the need for more research on diagnosing and treating EPSCC in rectal masses.
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  • Researchers are tackling the limitations of traditional RF spectrum analysis, which is restricted to about 1 GHz bandwidth due to the constraints of speed in analog-to-digital converters (ADCs).
  • They developed a new optical RF spectrum analyzer that uses optical methods to allow for continuous monitoring of a much larger bandwidth (15 GHz) and a rapid update rate of 385 kHz.
  • This system employs advanced techniques such as Rayleigh backscattering and a dual-resolution scheme to optimize performance, making it a significant advancement for applications in wireless communication and RADAR technology.
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Electronic analog to digital converters (ADCs) are running up against the well-known bit depth versus bandwidth trade off. Towards this end, radio frequency (RF) photonic-enhanced ADCs have been the subject of interest for some time. Optical frequency comb technology has been used as a workhorse underlying many of these architectures.

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  • Researchers developed a method to control optical frequency combs on a line-by-line basis using stimulated Brillouin scattering (SBS), which allows for precise manipulation without needing multiple dedicated lasers for each line.* -
  • Their new technique employs frequency shifting fiber optic loops to create both an optical frequency comb and a series of synchronized pulses, enabling complete comb control with just one seed laser.* -
  • They demonstrated their approach by manipulating a comb with 50 lines spaced 200 MHz apart and achieved a high modulation depth of 30 dB, indicating a scalable and efficient way to manage numerous comb teeth using typical fiber-optic components.*
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We use the drift-diffusion equations to calculate the responsivity of a modified uni-traveling carrier (MUTC) photodetector (PD) with a frequency comb input that is generated by a series of short optical pulses. We first use experimental results for the responsivity of the MUTC PD to obtain an empirical model of bleaching in pulsed mode. We incorporate our empirical bleaching model into a drift-diffusion model to calculate the impact of nonlinearity in an MUTC PD on RF-modulated electro-optic frequency combs.

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  • The study analyzes how nonlinearity affects two types of photodetectors (PDs)—a standard PD and a modified uni-traveling carrier (MUTC) PD—when using an RF-modulated frequency comb generated by 100-fs optical pulses.
  • It focuses on nonlinear saturation caused by high peak-to-average-power ratios and examines second- and third-order intermodulation distortion products (IMD2 and IMD3) for each comb line rather than just general signals.
  • Findings indicate that the MUTC PD experiences more significant nonlinear distortion at higher frequencies compared to the standard PD.
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Mucormycosis is a fatal opportunistic fungal infection. Rarely it can occur in immunocompetent patients. Here, we present a case of colonic mucormycosis in immunocompetent patients.

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We describe a procedure to calculate the impulse response and phase noise of high-current photodetectors using the drift-diffusion equations while avoiding computationally expensive Monte Carlo simulations. We apply this procedure to a modified uni-traveling-carrier (MUTC) photodetector. In our approach, we first use the full drift-diffusion equations to calculate the steady-state photodetector parameters.

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Mediastinal pancreatic pseudocyst (MPP) is a rare, but known, complication of both acute and chronic pancreatitis. Most pseudocysts are associated with alcoholic pancreatitis. Recent advances in endoscopic techniques have shown promising results, with reduced chances of infection and recurrence than with percutaneous drainage, but limited availability restricts widespread use.

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We introduce a novel technique for broadband RF disambiguation which exploits a known jitter imparted onto the sampling rate of an optical pulse source in a subsampled analog optical link. Coarse disambiguation to bandwidths equal to the sample rate is achieved using pure tones as example waveforms by comparing the amplitude of the jitter-induced sidebands relative to the measured signal within the fundamental Nyquist band (frep/2). This sampling technique allows for ultra-wideband signal recovery with a single measurement.

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We provide the first experimental demonstration of the impact of bias-frequency on second-order distortion in sampled analog optical links. We show proper selection of bias frequency yields >48 dB improvement in second-order distortion performance. In addition, we demonstrate that measurement of the average frequency of the optical comb may be used to determine the optimum bias frequency - without the need for involved radio-frequency distortion measurements.

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Histoplasmosis is an endemic infection of the Ohio and Mississippi River valleys. Clinical presentation of infection in immunocompetent hosts ranges from asymptomatic to minor flu-like symptoms; however, disseminated infection can occur in immunocompromised patients. Esophageal involvement in the form of dysphagia secondary to mediastinal histoplasmosis is rarely reported in the literature.

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A new technique to cancel photodiode-induced even-order distortion in microwave photonic links is demonstrated. A single Mach-Zehnder modulator, biased slightly away from the quadrature point, is shown to suppress photodiode second-order intermodulation distortion in excess of 40 dB without affecting the fundamental power. The technique is theoretically described with supporting experimental results.

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Colorectal cancer is one of the leading causes of cancer related deaths in western world. While most common site for metastasis for colon cancer is liver, lung, and the peritoneum, metastasis to various other organs such as brain, bones and thyroid has been reported. Metastatic lesions to the small bowel are more common than primary lesions and most common primary neoplasms that metastasize to the duodenum are lung cancer, renal cell carcinoma, breast cancer, and malignant melanoma.

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In this proof-of-concept study, high-resolution melt curve (HRMC) analysis was investigated as a postquantification screening tool to discriminate human CSF1PO and THO1 genotypes amplified with mini-STR primers in the presence of SYBR Green or LCGreen Plus dyes. A total of 12 CSF1PO and 11 HUMTHO1 genotypes were analyzed on the LightScanner HR96 and LS-32 systems and were correctly differentiated based upon their respective melt profiles. Short STR amplicon melt curves were affected by repeat number, and single-source and mixed DNA samples were additionally differentiated by the formation of heteroduplexes.

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Despite efforts to reduce malaria morbidity and mortality, drug-resistant parasites continue to evade control strategies. Recently, emphasis has shifted away from control and toward regional elimination and global eradication of malaria. Such a campaign requires tools to monitor genetic changes in the parasite that could compromise the effectiveness of antimalarial drugs and undermine eradication programs.

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BACKGROUND: Total cholesterol was among the earliest identified risk factors for coronary heart disease (CHD). We sought to identify genetic variants in six genes associated with lipid metabolism and estimate their respective contribution to risk for CHD. METHODS: For 6 lipid-associated genes (LCAT, CETP, LIPC, LPL, SCARB1, and ApoF) we scanned exons, 5' and 3' untranslated regions, and donor and acceptor splice sites for variants using Hi-Res Melting® curve analysis (HRMCA) with confirmation by cycle sequencing.

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Article Synopsis
  • - The study investigates the connection between vitamin D deficiency and ICU outcomes in veterans, revealing that many had insufficient levels, with 38% classified as deficient (<20 ng/mL).
  • - ICU survivors generally had lower rates of vitamin D deficiency compared to nonsurvivors, indicating a significant correlation between higher deficiency and longer ICU stays, as well as increased mortality risk.
  • - The findings suggest that maintaining adequate vitamin D levels might improve ICU patient outcomes and reduce healthcare costs, prompting recommendations to routinely check and address vitamin D deficiencies in these patients.
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Background: asthma and obesity continue to have a significant effect on public health. It is widely accepted that obesity may be an independent risk factor for asthma and affect asthma severity and quality of life (QOL).

Objective: to examine the relationship between body mass index (BMI [calculated as weight in kilograms divided by height in meters squared]) and asthma severity, spirometry findings, health care utilization (HCU), and QOL.

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  • Pharmacogenetic testing is increasingly used, but there is a lack of quality control materials covering important genetic variations typically assessed.
  • The CDC's Genetic Testing Reference Material Coordination Program has created a panel of 107 genomic DNA reference materials focusing on five key gene loci commonly included in these tests.
  • The study found consistent results across multiple laboratories, with variations arising mainly from assay design and nomenclature, and additional testing of nine other pharmacogenetic loci was also conducted.
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Objective: The aim of this study is to discover common variants in 6 lipid metabolic genes and construct and validate a genetic risk score (GRS) based on the joint effects of genetic variants in multiple genes from lipid and other pathobiologic pathways.

Background: Explaining the genetic basis of coronary artery disease (CAD) is incomplete. Discovery and aggregation of genetic variants from multiple pathways may advance this objective.

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Warfarin anticoagulation is complicated by the highly variable inter-individual response. Approximately 50% of the dose variability arises from clinical factors and variants in two genes, CYP2C9 (*2 and *3 variants) and VKORC1 -1173 C > T. We tested variants in five additional genes (EPHX1, PROC, APOE, CYP4F2, CALU and a new variant in VKORC1 in an attempt to further reduce the variability in predicted stable warfarin dose.

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Warfarin anticoagulation therapy is complicated by its narrow therapeutic index and by wide inter-individual differences in dosing requirements arising, in part, from genetic factors. The present report describes the development, validation and feasibility testing of a rapid genotyping assay that concurrently detects the CYP2C9*2 and *3 variants along with the VKORC1 C1173T polymorphism. The study employed melting curve analysis using labeled probes and compared two detection instruments (the HR-1 and the R.

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