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1.
J Acoust Soc Am ; 147(4): 2205, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32359314

ABSTRACT

An analysis is presented for the evaluation of the acoustic field of a rotating source in a non-uniform potential flow. Other than the restriction to low flow Mach numbers, the method is exact and general. The variation in radiation properties with source position is handled by representation as a Fourier series in source angle, giving rise to an asymmetrically varying acoustic field evaluated by summation of the series. The method is used to develop an exact solution for the model problem of a rotor operating near a cylinder in cross-flow and sample calculations demonstrate the accuracy of the technique when compared to full numerical evaluation. The calculations show changes of greater than one decibel in the acoustic field due to flow non-uniformity at a flow Mach number of 0.15, a typical speed for propeller aircraft at take-off.

2.
J Acoust Soc Am ; 143(3): 1623, 2018 03.
Article in English | MEDLINE | ID: mdl-29604667

ABSTRACT

A method is presented for the computation of the acoustic field around a tonal circular source, such as a rotor or propeller, based on an exact formulation which is valid in the near and far fields. The only input data required are the pressure field sampled on a cylindrical surface surrounding the source, with no requirement for acoustic velocity or pressure gradient information. The formulation is approximated with exponentially small errors and appears to require input data at a theoretically minimal number of points. The approach is tested numerically, with and without added noise, and demonstrates excellent performance, especially when compared to extrapolation using a far-field assumption.

3.
J Acoust Soc Am ; 140(5): 3963, 2016 11.
Article in English | MEDLINE | ID: mdl-27908049

ABSTRACT

A method for the fast evaluation of time-dependent acoustic fields from complex sources is presented. The technique is based on a fast integration method for the boundary integral arising in a Kirchhoff formulation and requires a small, and roughly constant, computation time to compute a transient signal, at the expense of a pre-processing stage. In the calculations in this paper, based on test cases for a single rotor, a counter-rotating open rotor, and a broadband volume source, it is found that transient field calculations require an order of magnitude less computational time for the field from an array of 16 384 sources, a computational advantage that increases with source number.

4.
J Acoust Soc Am ; 139(2): 630-5, 2016 02.
Article in English | MEDLINE | ID: mdl-26936547

ABSTRACT

The efficient computation of transient fields radiated by non-harmonic source distributions is a problem relevant in numerous areas of acoustics. This paper presents an efficient easily implemented method for the generation of time-dependent spherical harmonic expansions for arbitrary sources, which can be used to compute the transient radiated field at arbitrary points outside the source domain. The method depends on the theory of time-domain spherical harmonic expansions and the solution of Vandermonde systems. Results are presented demonstrating the efficiency and accuracy of the method with respect to full evaluation of the field radiated by a randomized source distribution.

5.
Genome Med ; 6(11): 98, 2014.
Article in English | MEDLINE | ID: mdl-25520755

ABSTRACT

BACKGROUND: Dendritic cells localize throughout the body, where they can sense and capture invading pathogens to induce protective immunity. Hence, harnessing the biology of tissue-resident dendritic cells is fundamental for the rational design of vaccines against pathogens. METHODS: Herein, we characterized the transcriptomes of four antigen-presenting cell subsets from the human vagina (Langerhans cells, CD14(-) and CD14(+) dendritic cells, macrophages) by microarray, at both the transcript and network level, and compared them to those of three skin dendritic cell subsets and blood myeloid dendritic cells. RESULTS: We found that genomic fingerprints of antigen-presenting cells are significantly influenced by the tissue of origin as well as by individual subsets. Nonetheless, CD14(+) populations from both vagina and skin are geared towards innate immunity and pro-inflammatory responses, whereas CD14(-) populations, particularly skin and vaginal Langerhans cells, and vaginal CD14(-) dendritic cells, display both Th2-inducing and regulatory phenotypes. We also identified new phenotypic and functional biomarkers of vaginal antigen-presenting cell subsets. CONCLUSIONS: We provide a transcriptional database of 87 microarray samples spanning eight antigen-presenting cell populations in the human vagina, skin and blood. Altogether, these data provide molecular information that will further help characterize human tissue antigen-presenting cell lineages and their functions. Data from this study can guide the design of mucosal vaccines against sexually transmitted pathogens.

6.
Microb Pathog ; 58: 35-44, 2013 May.
Article in English | MEDLINE | ID: mdl-23201532

ABSTRACT

Dendritic cells (DCs) are major antigen presenting cells (APCs) that can initiate and control host immune responses toward either immunity or tolerance. These features of DCs, as immune orchestrators, are well characterized by their tissue localizations as well as by their subset-dependent functional specialties and plasticity. Thus, the level of protective immunity to invading microbial pathogens can be dependent on the subsets of DCs taking up microbial antigens and their functional plasticity in response to microbial products, host cellular components and the cytokine milieu in the microenvironment. Vaccines are the most efficient and cost-effective preventive medicine against infectious diseases. However, major challenges still remain for the diseases caused by sexually-transmitted pathogens, including HIV, HPV, HSV and Chlamydia. We surmise that the establishment of protective immunity in the female genital mucosa, the major entry and transfer site of these pathogens, will bring significant benefit for the protection against sexually-transmitted diseases. Recent progresses made in DC biology suggest that vaccines designed to target proper DC subsets may permit us to establish protective immunity in the female genital mucosa against sexually-transmitted pathogens.


Subject(s)
Bacterial Vaccines/immunology , Dendritic Cells/immunology , Genitalia, Female/immunology , Immunity, Mucosal , Sexually Transmitted Diseases/immunology , Sexually Transmitted Diseases/prevention & control , Viral Vaccines/immunology , Bacterial Vaccines/genetics , Drug Discovery/trends , Female , Humans , Viral Vaccines/genetics
7.
J Acoust Soc Am ; 129(2): 633-41, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21361422

ABSTRACT

An analysis is developed linking the form of the sound field from a circular source to the radial structure of the source, without recourse to far-field or other approximations. It is found that the information radiated into the field is limited, with the limit fixed by the wavenumber of the source multiplied by the source radius (Helmholtz number). The acoustic field is found in terms of the elementary fields generated by a set of line sources whose form is given by Chebyshev polynomials of the second kind and whose amplitude is found to be given by weighted integrals of the radial source term. The analysis is developed for tonal sources, such as rotors, and for Helmholtz number less than two, for random disk sources. In this case, the analysis yields the cross-spectrum between two points in the acoustic field. The analysis is applied to the problems of tonal radiation, random source radiation as a model problem for jet noise, and to noise cancellation, as in active control of noise from rotors. It is found that the approach gives an accurate model for the radiation problem and explicitly identifies those parts of a source which radiate.


Subject(s)
Acoustics , Models, Theoretical , Noise , Sound , Acoustics/instrumentation , Equipment Design , Motion , Rotation
8.
J Acoust Soc Am ; 128(4): 1679-84, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20968340

ABSTRACT

The information content of a spinning sound field is analyzed using a combination of exact and asymptotic results, in order to set limits on how accurately source identification can be carried out. Using a transformation of the circular source to an exactly equivalent set of line source modes, given by Chebyshev polynomials, it is found that the line source modes of order greater than the source wavenumber generate exponentially small fields. Asymptotic analysis shows that the remaining, lower order, modes radiate efficiently only into a region around the source plane, with this region shrinking as the mode order is increased. The results explain the ill-conditioning of source identification methods; the successful use of low order models in active noise control; and the low radiation efficiency of subsonic jets.


Subject(s)
Acoustics , Models, Statistical , Sound , Aircraft , Fourier Analysis , Motion , Noise, Transportation , Numerical Analysis, Computer-Assisted , Pressure , Signal Processing, Computer-Assisted , Vibration
9.
J Acoust Soc Am ; 128(6): 3375-80, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21218871

ABSTRACT

An exact series expansion for the field radiated by a monopole ring source with angular variation in source strength is derived from a previously developed expression for the field from a finite disk. The derived series can be used throughout the field, via the use of a reciprocity relation, and can be readily integrated to find the field radiated by arbitrary circular sources of finite extent, and differentiated to find the field due to higher order sources such as dipoles and quadrupoles.


Subject(s)
Acoustics/instrumentation , Models, Theoretical , Signal Processing, Computer-Assisted , Sound , Computer Simulation , Equipment Design , Motion , Numerical Analysis, Computer-Assisted , Time Factors
10.
J Acoust Soc Am ; 125(2): 690-7, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19206846

ABSTRACT

A method is presented for the reconstruction of rotating monopole source distributions using acoustic pressures measured on a sideline parallel to the source axis. The method requires no a priori assumptions about the source other than that its strength at the frequency of interest varies sinusoidally in azimuth on the source disk so that the radiated acoustic field is composed of a single circumferential mode. When multiple azimuthal modes are present, the acoustic field can be decomposed into azimuthal modes and the method applied to each mode in sequence. The method proceeds in two stages, first finding an intermediate line source derived from the source distribution and then inverting this line source to find the radial variation in source strength. A far-field form of the radiation integrals is derived, showing that the far-field pressure is a band-limited Fourier transform of the line source, establishing a limit on the quality of source reconstruction, which can be achieved using far-field measurements. The method is applied to simulated data representing wind-tunnel testing of a ducted rotor system (tip Mach number of 0.74) and to control of noise from an automotive cooling fan (tip Mach number of 0.14), studies which have appeared in the literature of source identification.


Subject(s)
Acoustics , Models, Theoretical , Sound , Algorithms , Computer Simulation , Motion , Numerical Analysis, Computer-Assisted , Pressure , Rotation
11.
Obstet Gynecol ; 102(3): 524-6, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12962936

ABSTRACT

BACKGROUND: Patients may present with post-hysterectomy vaginal vault prolapse in conjunction with small bowel obstruction. Prior pelvic surgery, malignancy, and radiation therapy may be associated with this presentation. CASE: An 83-year-old multiparous woman with a history of poorly differentiated endometrial adenocarcinoma was treated with radiation therapy, total abdominal hysterectomy, and salpingo-oophorectomy. Anterior exenteration was performed for a recurrence. Seventeen years after her last pelvic operation, she had small bowel obstruction that coincided with a worsening post-hysterectomy vaginal vault prolapse. Surgical management included a side-to-side ileoileostomy and excision with closure of the vaginal apex. CONCLUSION: Although pelvic organ prolapse primarily affects quality of life, clinicians should be alert for bowel obstruction occurring with post-hysterectomy vaginal vault prolapse.


Subject(s)
Hysterectomy/adverse effects , Intestinal Obstruction/surgery , Ovariectomy/adverse effects , Uterine Prolapse/surgery , Adenocarcinoma/pathology , Adenocarcinoma/radiotherapy , Adenocarcinoma/surgery , Aged , Aged, 80 and over , Endometrial Neoplasms/pathology , Endometrial Neoplasms/radiotherapy , Endometrial Neoplasms/surgery , Female , Follow-Up Studies , Humans , Hysterectomy/methods , Intestinal Obstruction/complications , Intestinal Obstruction/etiology , Intestine, Small , Laparotomy/methods , Ovariectomy/methods , Postoperative Complications/diagnosis , Postoperative Complications/surgery , Radiation Injuries/diagnosis , Radiation Injuries/surgery , Risk Assessment , Treatment Outcome , Uterine Prolapse/complications , Uterine Prolapse/etiology
12.
Article in English | MEDLINE | ID: mdl-12851760

ABSTRACT

Estrogen receptors are present in the urogenital tract. However, little is known about the quantitative distribution of the traditional estrogen receptor (ERalpha) mRNA and the recently identified ERbeta mRNA. By quantitative reverse transcription polymerase chain reaction analysis, the distributions of ERalpha and ERbeta mRNA in mouse urogenital tissues and their expression in selected urogenital tissues after oophorectomy, with or without estrogen replacement, were evaluated. ERalpha mRNA concentrations were higher in the ovary, oviduct, uterus and vagina than in the kidney, ureter or bladder ( P<0.05); ERbeta transcripts were highest in the ovary, oviduct and bladder ( P<0.05). After oophorectomy and estrogen replacement, significant changes were identified in ERalpha and ERbeta mRNA expression. ERalpha and ERbeta mRNA are differentially expressed in mouse urogenital tissues. Oophorectomy and estrogen replacement affect estrogen receptors differently in the bladder, vagina and uterus. These results may explain some tissue-specific responses to estrogen and selective estrogen receptor modulators. The mRNA distributions of estrogen receptors alpha and beta and their expression after oophorectomy, with or without estrogen replacement, differ in mouse urogenital tissues.


Subject(s)
Estrogen Replacement Therapy , Ovariectomy/veterinary , Receptors, Estrogen/analysis , Receptors, Estrogen/biosynthesis , Urogenital System/physiology , Animals , Estrogen Receptor alpha , Estrogen Receptor beta , Female , Gene Expression Regulation , Mice , RNA, Messenger/analysis , RNA, Messenger/biosynthesis , Reverse Transcriptase Polymerase Chain Reaction
13.
J Reprod Med ; 47(11): 939-42, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12497686

ABSTRACT

BACKGROUND: Urethral prolapse is frequently encountered in girls. Although its occurrence in elderly women is not rare, little published information exists regarding this clinical condition or its management. CASE: A 90-year-old woman (gravida 1, para 1) with a four-year history of intermittent vaginal bleeding had both urethral and uterovaginal prolapse. The condition was initially managed conservatively with estrogen and a pessary. Ultimately, surgical intervention was required for complete resolution. CONCLUSION: Urethral prolapse can occur in elderly women and may present concomitantly with other forms of pelvic floor dysfunction such as uterovaginal prolapse. Conservative treatment with estrogen is partially effective in reducing the size of the urethral prolapse and may point to hypoestrogenism as one potential cause of this condition in elderly women. However, surgical management may ultimately be required for complete resolution of these problems, even in medically compromised patients.


Subject(s)
Urethral Diseases/diagnosis , Uterine Prolapse/diagnosis , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Humans , Pessaries , Urethral Diseases/complications , Urethral Diseases/pathology , Urethral Diseases/surgery , Uterine Prolapse/complications , Uterine Prolapse/pathology , Uterine Prolapse/surgery
14.
Am J Obstet Gynecol ; 187(2): 430-3, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12193938

ABSTRACT

OBJECTIVE: This study was undertaken to determine the incidence of clinically overt postpartum urinary retention after vaginal delivery and to examine what maternal, fetal, and obstetric factors are associated with this problem. STUDY DESIGN: This was a retrospective case-controlled study of women who had overt postpartum urinary retention after vaginal delivery from August 1992 through April 2000. RESULTS: Fifty-one of 11,332 (0.45%) vaginal deliveries were complicated by clinically overt postpartum urinary retention. In most cases (80.4%), the problem had resolved before hospital dismissal. Persons with urinary retention were more likely than control subjects to be primiparous (66.7% vs 40.0%; P <.001), to have had an instrument-assisted delivery (47.1% vs 12.4%; P <.001), to have received regional analgesia (98.0% vs 68.8%; P <.001), and to have had a mediolateral episiotomy (39.2% vs 12.5%; P <.001). On multivariate logistic regression analysis, of these 4 variables, only instrument-assisted delivery and regional analgesia were significant independent risk factors. CONCLUSION: Clinically overt postpartum urinary retention complicates approximately 1 in 200 vaginal deliveries, with most resolving before hospital dismissal. Factors that are independently associated with its occurrence include instrument-assisted delivery and regional analgesia.


Subject(s)
Obstetric Labor Complications/physiopathology , Urinary Retention/physiopathology , Adult , Analgesia, Epidural/adverse effects , Case-Control Studies , Episiotomy/adverse effects , Female , Humans , Obstetrical Forceps/adverse effects , Parity , Pregnancy , Retrospective Studies , Risk Factors , Urinary Retention/etiology , Vacuum Extraction, Obstetrical/adverse effects
15.
J Am Assoc Gynecol Laparosc ; 9(3): 321-6, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12101329

ABSTRACT

STUDY OBJECTIVE: To compare operative characteristics and charges of laparoscopy and laparotomy for women with a benign unilateral adnexal mass 7 cm or less in greatest diameter. DESIGN: Historical cohort study (Canadian Task Force classification II-2). SETTING: Clinic department of obstetrics and gynecology. PATIENTS: One hundred six women. INTERVENTION: Unilateral oophorectomy or unilateral salpingo-oophorectomy performed by laparoscopy or laparotomy. MEASUREMENTS AND MAIN RESULTS: When patients were compared on an intent to treat basis, no differences in greatest mass diameter (4.2 vs 4.5 cm), patient age (49.2 vs 46.4 yrs), or body mass index (26.0 vs 27.0 kg/m(2)) were found between 62 laparoscopies and 44 laparotomies. Laparoscopy was associated with longer operating times (94 vs 63 min, p <0.001), shorter hospital stay (1.6 vs 2.5 days, p <0.001), higher sterile supply charges ($1031 vs $40, p <0.001), and lower hospital room charges ($672 vs $1351, p <0.0001). No significant differences in total hospital charges, febrile morbidity, or transfusion rates were identified. CONCLUSION: Patient charges and early operative morbidity are similar for laparoscopy and laparotomy. Therefore, patient and surgeon preference should be a primary consideration when deciding on operative approach in carefully selected women with a unilateral adnexal mass.


Subject(s)
Adnexal Diseases/surgery , Gynecologic Surgical Procedures/methods , Laparoscopy , Laparotomy , Adnexal Diseases/diagnosis , Adnexal Diseases/economics , Aged , Female , Hospital Charges , Humans , Laparoscopy/economics , Laparotomy/economics , Middle Aged , Treatment Outcome
16.
Am J Obstet Gynecol ; 187(1): 103-6, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12114896

ABSTRACT

OBJECTIVE: This investigation was undertaken to determine whether the sensory neuron adenosine triphosphate receptor subunit (P2X(3)) messenger RNA expression is altered in female mouse bladders after surgical oophorectomy with or without estrogen replacement. STUDY DESIGN: The mean relative concentrations of the P2X(3) receptor in 30 female mouse bladders (10 sham operated, 10 oophorectomized, and 10 oophorectomized with estrogen replacement) were determined with quantitative reverse transcription-polymerase chain reaction analysis. RESULTS: P2X(3) expression increased after surgical oophorectomy (0.91 +/- 0.16 vs 1.04 +/- 0.11, P =.048). However, P2X(3) expression after oophorectomy and immediate estrogen replacement did not differ from that of oophorectomy alone (1.11 +/- 0.15 vs 1.04 +/- 0.11, P =.206). CONCLUSIONS: The P2X(3) sensory neuron receptor messenger RNA expression is increased after oophorectomy but is not influenced by subsequent estrogen replacement. This has clinical significance because sensory neuron receptors may be associated with certain forms of bladder dysfunction.


Subject(s)
Estradiol/physiology , Receptors, Purinergic P2/metabolism , Urinary Bladder/metabolism , Animals , Estrogen Replacement Therapy , Female , Gene Expression , Mice , Ovariectomy , RNA, Messenger/genetics , Receptors, Purinergic P2/genetics , Receptors, Purinergic P2X3 , Reverse Transcriptase Polymerase Chain Reaction
17.
Am J Obstet Gynecol ; 186(5): 866-8, 2002 May.
Article in English | MEDLINE | ID: mdl-12015497

ABSTRACT

OBJECTIVE: We sought to compare characteristics of patients with urodynamically diagnosed detrusor instability or genuine stress incontinence. STUDY DESIGN: A retrospective audit of 293 consecutive women who were referred to a urogynecologist for evaluation of urinary incontinence between June 1996 and April 2000. RESULTS: Of the 293 patients, 289 women had a physical examination and urodynamic testing, which revealed genuine stress incontinence (35%), detrusor instability (32%), mixed incontinence (29%), or normal urodynamic function (4%). Compared with patients with detrusor instability, those women with genuine stress incontinence were more likely to be white than African American (P <.0001) and to have a cystocele(P =.027), rectocele (P <.0001), or paravaginal defect (P =.004). No differences in age, gravidity, parity, estrogen treatment, or previous anti-incontinence procedure were identified between women with detrusor instability and women with genuine stress incontinence. CONCLUSION: In a tertiary referral center, the distribution of urinary incontinence is evenly divided among genuine stress incontinence, detrusor instability, and mixed incontinence. Patients with genuine stress incontinence are more likely to be white and to have pelvic floor prolapse and symptoms of pure stress incontinence.


Subject(s)
Urinary Bladder Diseases/diagnosis , Urinary Bladder Diseases/physiopathology , Urinary Incontinence, Stress/diagnosis , Urinary Incontinence, Stress/physiopathology , Urodynamics , Adult , Black or African American , Aged , Black People , Female , Humans , Middle Aged , Urinary Bladder Diseases/complications , Urinary Bladder Diseases/ethnology , Urinary Incontinence/diagnosis , Urinary Incontinence/ethnology , Urinary Incontinence/physiopathology , Urinary Incontinence, Stress/complications , Urinary Incontinence, Stress/ethnology , White People
18.
J Reprod Med ; 47(4): 249-52, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12012874

ABSTRACT

OBJECTIVE: To review recent literature that examines the histologic characterization of women with atypical glandular cells of undermined significance (AGUS) on a Pap smear. STUDY DESIGN: The English-language literature published between January 1995 and April 2000 was reviewed. The MEDLINE database and the search terms atypical glandular cells of undetermined significance and AGUS were used. The references cited in the studies were reviewed to identify additional publications. Studies that reported data from patients with a cytologic diagnosis of AGUS without an associated squamous lesion identified by Pap smear were used to summarize the final histologic diagnoses. RESULTS: Eight percent of women with the diagnosis of an AGUS Pap smear without a concurrent squamous lesion had a malignancy. CONCLUSION: A thorough initial evaluation is recommended for all women with a cytologic diagnosis of AGUS.


Subject(s)
Cervix Uteri/pathology , Neoplasms, Glandular and Epithelial/pathology , Uterine Neoplasms/pathology , Female , Humans , Papanicolaou Test , Predictive Value of Tests , Reproducibility of Results , Vaginal Smears
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