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1.
Rep Prog Phys ; 87(7)2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38899371

ABSTRACT

The Brillouin sphere is defined as the smallest sphere, centered at the origin of the geocentric coordinate system, that incorporates all the condensed matter composing the planet. The Brillouin sphere touches the Earth at a single point, and the radial line that begins at the origin and passes through that point is called the singular radial line. For about 60 years there has been a persistent anxiety about whether or not a spherical harmonic (SH) expansion of the external gravitational potential,V, will converge beneath the Brillouin sphere. Recently, it was proven that the probability of such convergence is zero. One of these proofs provided an asymptotic relation, called Costin's formula, for the upper bound,EN, on the absolute value of the prediction error,eN, of a SH series model,VN(θ,λ,r), truncated at some maximum degree,N=nmax. When the SH series is restricted to (or projected onto) a particular radial line, it reduces to a Taylor series (TS) in1/r. Costin's formula isEN≃BN-b(R/r)N, whereRis the radius of the Brillouin sphere. This formula depends on two positive parameters:b, which controls the decay of error amplitude as a function ofNwhenris fixed, and a scale factorB. We show here that Costin's formula derives from a similar asymptotic relation for the upper bound,Anon the absolute value of the TS coefficients,an, for the same radial line. This formula,An≃Kn-k, depends on degree,n, and two positive parameters,kandK, that are analogous tobandB. We use synthetic planets, for which we can compute the potential,V, and also the radial component of gravitational acceleration,gr=∂V/∂r, to hundreds of significant digits, to validate both of these asymptotic formulas. Let superscriptVrefer to asymptotic parameters associated with the coefficients and prediction errors for gravitational potential, and superscriptgto the coefficients and predictions errors associated withgr. For polyhedral planets of uniform density we show thatbV=kV=7/2andbg=kg=5/2almost everywhere. We show that the frequency of oscillation (around zero) of the TS coefficients and the series prediction errors, for a given radial line, is controlled by the geocentric angle,α, between that radial line and the singular radial line. We also derive useful identities connectingKV,BV,Kg, andBg. These identities are expressed in terms of quotients of the various scale factors. The only other quantities involved in these identities areαandR. The phenomenology of 'series divergence' and prediction error (whenr < R) can be described as a function of the truncation degree,N, or the depth,d, beneath the Brillouin sphere. For a fixedr⩽R, asNincreases from very low values, the upper error boundENshrinks until it reaches its minimum (best) value whenNreaches some particular or optimum value,Nopt. WhenN>Nopt, prediction error grows asNcontinues to increase. Eventually, whenN≫Nopt, prediction errors increase exponentially with risingN. If we fix the value ofNand allowR/rto vary, then we find that prediction error in free space beneath the Brillouin sphere increases exponentially with depth,d, beneath the Brillouin sphere. Becausebg=bV-1everywhere, divergence driven prediction error intensifies more rapidly forgrthan forV, both in terms of its dependence onNandd. If we fix bothNandd, and focus on the 'lateral' variations in prediction error, we observe that divergence and prediction error tend to increase (as doesB) as we approach high-amplitude topography.

2.
Ir Med J ; 116(No.1): 10, 2023 01 19.
Article in English | MEDLINE | ID: mdl-36916759

ABSTRACT

The virtual fracture clinic (VFC) enables the safe, cost-effective delivery of high-quality patient-centred fracture care, whilst reducing hospital footfall. Within our institution, an Outreach VFC was launched, accepting a pre-defined range of trauma referrals from the outreach centre's emergency department (ED). The initial nine months' worth of cases referred to the Outreach VFC were assessed. The injury pattern, time to review, treatment plan and discharge destination of each referred patient were examined. A total of 822 patients were referred to the Outreach VFC during its initial nine months in operation. Owing to COVID-19-related alterations in the patient pathway, 58.1% of patients were referred on to fracture clinic/ED, with 34.4% of patients being referred for physiotherapy input. 44.9% of patients were reviewed at the Outreach VFC within 72 hours of ED presentation, with 88.6% of patients reviewed within 7 days. The Outreach VFC pilot initiative saved the Dublin Midlands Hospitals Group approximately €83,022 over nine months. The Outreach VFC model represents a novel approach to trauma care delivery with advantages for patient and hospital alike. Rural communities serve to benefit from its future implementation and the remote management of orthopaedic trauma. The Outreach VFC model provides a means of delivering safe and timely orthopaedic care whilst maintaining high levels of patient satisfaction.


Subject(s)
COVID-19 , Fractures, Bone , Humans , Fractures, Bone/therapy , Ambulatory Care Facilities , Patient Satisfaction , Referral and Consultation
3.
Br J Cancer ; 109(8): 2131-41, 2013 Oct 15.
Article in English | MEDLINE | ID: mdl-24052043

ABSTRACT

BACKGROUND: Taxanes are routinely used for the treatment of prostate cancer, however the majority of patients eventually develop resistance. We investigated the potential efficacy of EL102, a novel toluidine sulphonamide, in pre-clinical models of prostate cancer. METHODS: The effect of EL102 and/or docetaxel on PC-3, DU145, 22Rv1 and CWR22 prostate cancer cells was assessed using cell viability, cell cycle analysis and PARP cleavage assays. Tubulin polymerisation and immunofluorescence assays were used to assess tubulin dynamics. CWR22 xenograft murine model was used to assess effects on tumour proliferation. Multidrug-resistant lung cancer DLKPA was used to assess EL102 in a MDR1-mediated drug resistance background. RESULTS: EL102 has in vitro activity against prostate cancer, characterised by accumulation in G2/M, induction of apoptosis, inhibition of Hif1α, and inhibition of tubulin polymerisation and decreased microtubule stability. In vivo, a combination of EL102 and docetaxel exhibits superior tumour inhibition. The DLKP cell line and multidrug-resistant DLKPA variant (which exhibits 205 to 691-fold greater resistance to docetaxel, paclitaxel, vincristine and doxorubicin) are equally sensitive to EL102. CONCLUSION: EL102 shows potential as both a single agent and within combination regimens for the treatment of prostate cancer, particularly in the chemoresistance setting.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Antineoplastic Agents/pharmacology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Prostatic Neoplasms/drug therapy , Sulfonamides/pharmacology , Toluidines/pharmacology , ATP Binding Cassette Transporter, Subfamily B , Animals , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Docetaxel , Dose-Response Relationship, Drug , Drug Resistance, Neoplasm , Drug Screening Assays, Antitumor , Drug Synergism , Humans , Male , Mice , Microtubules/drug effects , Microtubules/metabolism , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Random Allocation , Sulfonamides/administration & dosage , Taxoids/administration & dosage , Toluidines/administration & dosage , Tubulin/metabolism , Xenograft Model Antitumor Assays
4.
Phys Rev Lett ; 102(15): 150404, 2009 Apr 17.
Article in English | MEDLINE | ID: mdl-19518608

ABSTRACT

We investigate electron-positron pair production from vacuum for short laser pulses with a subcycle structure, in the nonperturbative regime (Schwinger pair production). We use the nonequilibrium quantum kinetic approach and show that the momentum spectrum of the created electron-positron pairs is extremely sensitive to the subcycle dynamics-depending on the laser frequency omega, the pulse length tau, and the carrier phase varphi-and shows several distinctive new signatures. This observation could not only help in the design of laser pulses to optimize the experimental signature of Schwinger pair production but also ultimately lead to new probes of light pulses at extremely short time scales.

5.
Food Microbiol ; 24(3): 301-4, 2007 May.
Article in English | MEDLINE | ID: mdl-17188209

ABSTRACT

The aim of this research was to identify the risk factors associated with the transfer of bacterial contamination from the fleece to the ovine carcass thereby providing the scientific basis for the development and validation of a clean sheep policy. Two hundred sheep in lairage were graded into five categories each consisting of 40 sheep. The categories were as follows; (A) clean and dry; (B) clean and wet; (C) dirty and dry; (D) dirty and wet and (E) visible dags (dung-clotted tufts of wool) categorized by the chief veterinary inspector at the slaughter plant based on the visual inspection of the hygienic status of the fleece. Microbiological evaluations of the carcasses were conducted using swab sampling methods. Total viable counts (TVCs), Enterobacteriaceae and coliform counts were obtained from 40 animals per category at four separate sites (brisket, shoulder, flank and rump) immediately after pelt removal. Statistical analysis of TVC data obtained from the carcass indicated that the dirt level of the fleece had a significant effect on contamination levels when the fleece was dry. Enterobacteriaceae and coliform counts suggest that dirt was a contributing risk factor regardless of wetness or dryness of the animal. The clean sheep policy should therefore differentiate between clean and dirty sheep and mandate additional hygiene measures for the latter.


Subject(s)
Abattoirs/standards , Food Handling/methods , Hygiene , Legislation, Food , Sheep/microbiology , Animals , Colony Count, Microbial , Consumer Product Safety , Humans , Hygiene/legislation & jurisprudence , Meat/microbiology , Meat/standards , Risk Factors
6.
Food Microbiol ; 23(8): 803-8, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16943086

ABSTRACT

The aim of this study was to design a thermal treatment(s) for pork luncheon roll, which would destroy Bacillus cereus and Clostridium perfringens vegetative cells and spores. B. cereus and C. perfringens vegetative and spore cocktails were used to inoculate luncheon meat. Samples were subjected to different temperatures and removal times. The decimal-reduction times (D-values) were calculated by linear regression analysis (D = -1/slope of a plot of log surviving cells versus time). The log(10) of the resulting D-values were plotted against their corresponding temperatures to calculate (-1/slope of the curve) the thermal resistance (z-values) of each cocktail. The D-values for vegetative cells ranged from 1 min (60 degrees C) to 33.2 min (50 degrees C) for B. cereus and from 0.9 min (65 degrees C) to 16.3 min (55 degrees C) for C. perfringens. The D-values for B. cereus spores ranged from 2.0 min (95 degrees C) to 32.1 min (85 degrees C) and from 2.2 min (100 degrees C) to 34.2 min (90 degrees C) for C. perfringens. The z-values were calculated to be 6.6 and 8.5 degrees C for B. cereus vegetative and spores, respectively, and 7.8 and 8.4 degrees C for C. perfringens vegetative cells and spores, respectively. The D-values of B. cereus and C. perfringens suggest that a mild cook of 70 degrees C for 12s and 1.3 min would achieve a 6 log reduction of B. cereus and C. perfringens vegetative cells, respectively. The equivalent reduction of B. cereus and C. perfringens spores would require the pork luncheon meat to be heated for 36 s at 105 and 110 degrees C, respectively. The results of this study provide the thermal inactivation data necessary to design a cooking protocol for pork luncheon roll that would inactivate B. cereus and C. perfringens vegetative cells and spores. The data may also be used in future risk assessment studies.


Subject(s)
Bacillus cereus/growth & development , Clostridium perfringens/growth & development , Food Preservation/methods , Hot Temperature , Meat Products/microbiology , Animals , Colony Count, Microbial , Consumer Product Safety , Food Contamination/analysis , Humans , Spores, Bacterial/growth & development , Swine , Time Factors
7.
Clin Otolaryngol ; 31(2): 160-2, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16620341

ABSTRACT

Radioiodine and thionamide treatment are the most frequently used treatment modalities for thyrotoxicosis in Europe and North America with surgery being reserved for selected cases. * In our clinic patients were offered all three modalities via simultaneous interview with an endocrinologist and a surgeon, with international risk benefit data for radioiodine and thionamide therapy, and local risk benefit data for total thyroidectomy provided. * When given the choice, at least 15% of patients opted for total thyroidectomy over the other modalities. * In our series of 100 consecutive surgical patients there was a 4% malignancy rate. * Total thyroidectomy should be offered equally, with radioiodine and thionamide treatment, as a first line treatment modality in the management of thyrotoxicosis.


Subject(s)
Antithyroid Agents/therapeutic use , Iodine Radioisotopes/therapeutic use , Thyroidectomy , Thyrotoxicosis/therapy , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Thyrotoxicosis/surgery , Treatment Outcome
8.
Phys Rev Lett ; 86(9): 1690-3, 2001 Feb 26.
Article in English | MEDLINE | ID: mdl-11290225

ABSTRACT

We show that while the zero temperature induced fermion number in a chiral sigma model background depends only on the asymptotic values of the chiral field, at finite temperature the induced fermion number depends also on the detailed shape of the chiral background. We resum the leading low temperature terms to all orders in the derivative expansion, producing a simple result that can be interpreted physically as the different effect of the chiral background on virtual pairs of the Dirac sea and on the real particles of the thermal plasma. By contrast, for a kink background, not of sigma model form, the finite T induced fermion number is temperature dependent but topological.

9.
J Lesbian Stud ; 2(4): 1-8, 1998.
Article in English | MEDLINE | ID: mdl-24785727
10.
Phys Rev D Part Fields ; 53(4): 2220-2226, 1996 Feb 15.
Article in English | MEDLINE | ID: mdl-10020211
12.
J Hum Lact ; 11(3): 217-8, 1995 Sep.
Article in English | MEDLINE | ID: mdl-7669243

ABSTRACT

Breastfeeding can be especially difficult for the physically challenged mother. This case report describes the challenges encountered by one disabled mother. A strong desire to succeed and a good support system, as well as being able to adapt to circumstances, formed the basis for success.


Subject(s)
Amputees/psychology , Breast Feeding , Mothers/psychology , Adaptation, Psychological , Adult , Amputees/education , Arm , Consultants , Female , Humans , Infant, Newborn , Leg , Male , Mothers/education
14.
Phys Rev D Part Fields ; 50(8): 5321-5328, 1994 Oct 15.
Article in English | MEDLINE | ID: mdl-10018182
15.
Phys Rev D Part Fields ; 48(12): 5721-5729, 1993 Dec 15.
Article in English | MEDLINE | ID: mdl-10016238
17.
Int J Partial Hosp ; 5(3): 215-23, 1988 Sep.
Article in English | MEDLINE | ID: mdl-10296332

ABSTRACT

Past studies examining the dropout from treatment phenomenon have failed to identify comparable populations or a standardized definition of the term "patient dropout." Although the phenomenon is widespread, few investigators have studied the problem within day-treatment programs serving subacutely disturbed clients in need of socialization or prevocational services. The primary purpose of the present study was to determine the reasons for brief Day Treatment Center (DTC) stays of 10 sessions or fewer and to ascertain implications of these findings for admission screening processes. Analysis of demographic information revealed that the average brief-stay patient was in his mid-thirties, was single (65%), was schizophrenic (39%) or suffering a mood disorder (27%), and had attended up to 4 days (63%) before leaving treatment. A retrospective review of 122 brief stay records revealed six categories of reasons for leaving the DTC: (1) a desire to return to work, (2) exacerbation of psychiatric symptoms, (3) resistance to treatment recommendations, (4) negative reaction to the treatment milieu, (5) a desire for less intense treatment, and (6) a belief that problems were resolved during the brief stay. The authors concluded that admission screening interviewers would benefit from complete past school and work records. Strategies for reducing dropout rates should include (1) longer transition periods for newly referred patients, (2) obligatory meetings with the patient and his family and therapist before inpatient discharge, and (3) improved orientation to the DTC program.


Subject(s)
Day Care, Medical/statistics & numerical data , Patient Dropouts/statistics & numerical data , Demography , Evaluation Studies as Topic , Hospital Bed Capacity, 300 to 499 , Hospitals, General/statistics & numerical data , New York City
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