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Nepal is an actively deforming region due to its tectonic setting that hosts many destructive earthquakes including the most recent 2015 Gorkha earthquake of magnitude 7.8. To better understand the physics of earthquakes and their precise location as well as monitoring of seismicity and real-time seismic hazard in the region, a highly resolved 3-D structure of the crust is essential. This study presents a new 3-D shear S -wave velocity structure of the crust using group and phase velocity dispersions obtained from ambient noise tomography. This study further constrains the discontinuities beneath Himalaya Nepal using teleseismic compressional P-wave coda autocorrelation. Our results show significant variation in the crustal structure within the region and correlate well with known geological and tectonic features present there. The results from the P-wave coda autocorrelation identify major seismic discontinuities in the crust including the Main Himalayan Thrust (MHT). The MHT with two ramps correlates well with a low S-wave velocity layer obtained from the ambient noise tomography. The first ramp agrees with the duplex structure in the MHT beneath Lesser Himalaya while the second ramp connects flat low velocity beneath High Himalaya to a broad low-velocity zone beneath South Tibet. Moreover, the High Himalaya low-velocity layer is located where the GPS data show creeping north of the coseismic rupture of the 2015 Gorkha earthquake. The lateral variation of S-wave velocity on the MHT surface provides the details of lateral transitions that might have potentially controlled the rupture pattern of the 2015 Gorkha earthquake.The geometry and extent of the High Himalaya low-velocity layer mimics the decollement coupling zone inferred from GPS data with widths of 50 to 70 km north of the nucleation of the 2015 Mw 7.8 Gorkha earthquake and 90 to 100 km north of the source of the Mw 8.4 1934 earthquake. The occurrence of millenary Mw>9.0 earthquakes in Central and Eastern Nepal would require either a wider coupling low velocity zone compared to the ones identified in this work or the involvement of southernmost Tibet low velocity decoupling zone so to store enough elastic energy.

We present a publicly available, open source version of the time-dependent, gas-grain chemical code UCLCHEM. UCLCHEM propagates the abundances of chemical species through a large network of chemical reactions in a variety of physical conditions. The model is described in detail, along with its applications. As an example of possible uses, UCLCHEM is used to explore the effect of protostellar collapse on commonly observed molecules, and study the behavior of molecules in C-type shocks. We find the collapse of a simple Bonnor–Ebert sphere successfully reproduces most of the behavior of CO, CS, and NH3 from cores observed by Tafalla et al. (2004), but cannot predict the behavior of N2H+. In the C-shock application, we find that molecules can be categorized such that they become useful observational tracers of shocks and their physical properties. Although many molecules are enhanced in shocked gas, we identify two groups of molecules in particular. A small number of molecules are enhanced by the sputtering of the ices as the shock propagates, and then remain high in abundance throughout the shock. A second, larger set is also enhanced by sputtering, but then destroyed as the gas temperature rises. Through these applications, the general applicability of UCLCHEM is demonstrated.

OBJECTIVE: To ascertain factors associated with HSV-1 and HSV-2 isolates in patients attending a genitourinary medicine clinic with symptomatic first episode genital herpes (FEGH). DESIGN: Retrospective study. SUBJECTS: A total of 606 females and 333 males presenting with culture positive FEGH between 1990-94. SETTING: Department of Genitourinary Medicine, Royal Hallamshire Hospital, Sheffield, UK. METHODS: Group comparison of referral patterns, demographic data, prior and concurrent episodes of STD, recent partner change. RESULTS: HSV-1 infected patients of either sex were more likely to be general practitioner (GP) referred, to be white, and less likely to have had preceding STD episodes. Recent sexual partner change had occurred significantly more often in HSV-2 infected females but there was no similar difference between HSV-1 and HSV-2 infected males. CONCLUSION: The relative HSV-1:HSV-2 isolate ratio in FEGH is influenced by the referral patterns. HSV-1 isolates predominate in patients presenting to GPs who refer the patients to GUM clinics for accurate diagnosis, counselling, follow up and screening for other STDs.

Crustal receiver functions have been calculated for a network of 51 three-component broadband seismometers distributed across the British Isles and NW Europe. Over 3200 receiver functions were assembled for 1055 events. For each station, preliminary estimates of crustal thickness and Vp/Vs ratio were obtained from H−κ plots. Stacked receiver functions were then inverted to determine shear wave velocity as a function of depth. Each result was checked by guided forward modelling and by Monte Carlo error analysis. In this way, the robustness of our final calculated velocity profiles was carefully tested. A set of depth migrated profiles was also constructed using an average of 50 events for each station over a range of backazimuths. These profiles agree well with legacy wide-angle crustal models. Our results show that crustal thickness varies between 24 and 36 km across the British Isles. Thicker crust is found beneath north Wales and beneath central Scotland. Thinner crust occurs beneath northwest Scotland and northwest Ireland. By combining our database with the results of controlled source, wide-angle experiments and with depth-converted reflection profiles, we have produced a detailed crustal thickness map for a region encompassing the British Isles. Our synthesis of crustal thickness and structure has important implications for the tectonic and magmatic histories of this region. Complex Moho structure with lower crustal P-wave velocities of >7 km s−1 occurs beneath regions of Cenozoic magmatism, which may be consistent with magmatic underplating. Thin crust beneath northern Britain suggests that present-day long wavelength topography is maintained by regional dynamic support, originating beneath the lithospheric plate.

In our study we determine the three dimensional Sv wave speed and azimuthal anisotropy model by analyzing vertical component multimode Rayleigh wave seismograms. We use data of broadband stations from in and around China. We construct the three dimensional model using a two step procedure. In the first step we use the automated version of the Cara and Leveque [1987] waveform inversion technique in terms of secondary observables for modeling each multimode Rayleigh waveform to determine the path-average mantle Sv wave speed structure. We have used the 3SMAC model (as a crustal part) and smooth version of PREM for the upper mantle velocity structure as an initial model. In the second stage we combine the 1-D velocity models in a tomographic inversion to obtain the three dimensional Sv wave speed structure and the azimuthal anisotropy as a function of depth. China is sitting at a triple junction of three major plates: the Eurasian plate, the Indo-Australian plate and the Philippine Sea plate. China itself has three major Precambian cratons: the North China craton (also called Sino-Korean craton), the Yangtze craton (also called South China craton) and the Tarim block. The interactions among different blocks have formed the tectonic features today and caused many intraplate earthquakes. These tectonics setting have made China an interesting place for various kind of study as all of these events have left their imprint on the upper mantle structure. It is generally agreed that the lithosphere is thick in west China while much of the lithospheric root was lost beneath some cratons in east China. Still it's an open debate whether the lithosphere beneath the Tibetan plateau has doubled its thickness as did the crust above or much of the thickened lithosphere was removed by mantle convection and delamination. The upper most part of our model is in good agreement with the finding from the deep seismic profile. It is also evident that the extent of crustal flow of Tibet is being restricted by Tarim in the north and Ordos, Sichuan in the east. Various receiver function and SS precursor results are also comparable with our results in terms of the lithosphere extent.

Numerous seismological experiments in central and southern Tibet have imaged the underthrusting Indian lithosphere and provided evidence of mid-crustal flow. A marked difference in mantle properties appears to occur in central Tibet, where body wave and Pn velocities become lower towards the north but with significant lateral variations. Surface wave studies tend to see velocities faster than the global average throughout Tibet in the deeper mantle (below ~150 km). Comparatively little seismological data had been collected in Northern Tibet. We combine data from the linear array of the INDEPTH-IV profile (2007-2008) and the ASCENT 2D deployment (2007-2009). We invert a high quality data set of more than 16,000 teleseismic P-wave arrival times and 3,100 teleseismic S-wave arrival times in a tomographic inversion to determine the velocity structure beneath NE Tibet in an area encompassing parts of the Qiangtang and Songpan-Ganzi terranes as well as the Kunlun Shan and part of the Qaidam. Major geological structures include the Kunlun Fault and the Jinsha and Bangong-Nujiang sutures. In total, 572 events at 80 stations were used for the P inversion, and 72 events for the S-inversion. Teleseismic regional tomography (ACH tomography) is most sensitive to lateral velocity contrasts, and in particular cannot resolve layer averages or very long range velocity variations; neither can it image variations in thickness or properties of the crust. In order to partially compensate for this, we utilise information from recent surface wave models, Acton et al (JGR, 2010) for the crust and shallow mantle, and a much extended version of the Priestley et al (JGR, 2006) model for the deeper mantle. The starting model for the body wave inversion combines both these models; in this way the well-established long wavelength background structure and absolute velocities provided by the surface waves are respected, but additional shorter range features can be imaged. For the P-wave starting model, we have translated the S-velocity variations into suitable P-velocities using a constant Vp/Vs ratio of 1.78. The resolution tests indicate that features more than a 100 km wide are reliably imaged throughout the study region; locally higher resolution is possible, but with significant smearing in the vertical direction. The resulting tomographic models show a number of large scale features. The lowest velocities are found below the Kunlun Shan, reaching depths of 300 km and more. There is a prominent high velocity zone extending across the south-west of the model below the Qiangtang terrane at approximately 130-220 km depth, whereas at shallower depths below the Qiangtang there appears to be more E-W variation. Further north, above 37°N, the velocity increases more smoothly with depth, and the high velocity zones are considerably less pronounced.

Summary: The management of cases of Chlamydia trachomatis genital infection diagnosed in clinics in Wessex in the last quarter of 1996 was surveyed, and the results compared with those obtained in the national gonorrhoea audit. Treatment regimens were extremely varied both between and within clinics. Overall, 71% of patients saw a health adviser, 74% returned for follow-up, and 96% of these were cured. Compared with the national gonorrhoea audit, fewer contacts were reported (1.2 vs 1.5), but more contacts were seen per index case (0.7 vs 0.5), and a higher proportion of contacts were seen (59% vs 33%). The figures were higher in those who returned for a test of cure. Little data were available for contacts attending elsewhere for treament; communication networks among genitourinary medicine (GUM) clinics are essential for effective contact tracing. Variations between clinics may reflect differences between the populations served as well as in diagnostic methods and management policies.

OBJECTIVE: To observe the composition of the vaginal flora of healthy women over time, and in relation to hormonal changes, sexual activity, and hygiene habits. DESIGN: A longitudinal surveillance of the vaginal flora over an eight week period. SUBJECTS: 26 female health care workers in local genitourinary medicine clinics. METHODS: The participants were anonymised. They filled in diary cards daily. Blind vaginal swabs were self-taken two-seven times weekly. A smear was air-dried for later Gram staining. The swabs were also cultured for Candida spp, Gardnerella vaginalis, anaerobes, Mycoplasma hominis and Ureaplasma urealyticum. RESULTS: Of 26 subjects, only four had normal vaginal microbiology throughout. One woman, who was not sexually active, had bacterial vaginosis (BV) throughout and nine (35%) had intermittent BV. Candidiasis was found intermittently in eight women (31%), and eight had normal microscopy. U urealyticum was isolated intermittently in 40% of women with BV, 25% with candida, and 50% with normal microscopy. Many women were symptomatic, but symptoms correlated poorly with microbiological findings. All but two women were sexually active; however, more women with BV were exposed to semen. BV seemed to be related to frequent use of scented soap, and there appeared to be an additive effect of clothing and hygiene factors. CONCLUSIONS: Our study raises doubts about what should be regarded as normal vaginal flora. It calls into question the significance of finding BV or U urealyticum on a single occasion in asymptomatic women, or of finding normal flora in symptomatic women. The effect of external factors on the vaginal flora deserve further study.

The hospital management of 108 HIV/AIDS patients cared for by the genitourinary medicine department, Sheffield, UK between 1984-93 was retrospectively studied to quantify the services utilized by these patients and to detail the management costs (1993 price) of outpatient (OP) services, inpatient (IP) care, investigational services and therapeutic provisions. The services utilized and cost are presented separately for the different clinical stages of the infection and as per patient year. Of the 108 patients, 95 (88%) were males and 13 (12%) females; most males (76.8%) acquired the infection through homosexual exposure, while 46% of females acquired it heterosexually. The mean number of OP consultation per asymptomatic, symptomatic non-AIDS and AIDS patient years were 11.6, 16.4 and 32.8 respectively; the mean number of IP episodes for each of these clinical groups were 0.15, 0.83 and 3.88 with IP stays 0.7, 3.5 and 40.6 days per patient year respectively. The annual costs of OP care (45.26 pounds per consultation), drugs and investigations were, respectively 525 pounds, 213 pounds and 153 pounds per asymptomatic patient year, 742 pounds, 2097 pounds and 224 pounds per symptomatic non-AIDS patient year and 1485 pounds, 2928 pounds and 382 pounds per AIDS patient year. The average annual OP drug cost per patient year showed little change since 1988. However, in the AIDS group, contributions from differing drug classes showed significant changes; while the contribution of antiretroviral drugs fell from 80.2% of the drug cost per AIDS patient year in 1990 to 31.3% in 1993, that from antibiotics rose from 0.3% in 1990 to 26.4% in 1993 and other antivirals from 9.4% in 1988 to 22.6% in 1993. These changes were related to lower recommended daily dosage of zidovudine and to wider prescription of antibiotics for atypical mycobacterial infections and domiciliary gancyclovir for CMV infection. The costs of annual mean IP care, IP drugs, IP investigations and IP procedures per AIDS patient year were 5926 pounds (146 pounds per IP stay), 2983 pounds, 282 pounds and 145 pounds respectively. The overall management cost of one AIDS patient year was 14,131 pounds and lifetime AIDS management cost, based on a mean survival of 17 months, a little more than 20,000 pounds. The annual management cost of an asymptomatic and symptomatic non-AIDS patient year is approximately 1/14th and 1/4th of the cost of an AIDS patient year.

Background The government set out a number of sexual health targets in the white paper “Choosing Health” 2004 and include. A reduction in the under 18 conception rate, An increase in the percentage of people aged 15–24 accepting chlamydia screening. Young people need to be able to easily access sexual health services in order to prevent, diagnose and treat sexually transmitted infections (STIs) and gain advice and contraception to protect against unintended pregnancy. A significant proportion of patients under the age of 16 are seen, who may have child protection concerns or be vulnerable. We wanted to examine the reasons for their attendance. Aims In female patients under the age of 16 attending the integrated sexual health clinic, to identify. The reasons for attendance. STI diagnosis and treatment. Contraceptive use and provision. The degree of sexual risk-taking in under 16s, including sexual history, condom use, requests for post coital contraception and pregnancy testing, and the number of pregnancies. Other child protection concerns, including age at first intercourse and age of sexual partner, and parental awareness of their sexual activity. Other factors that contribute to vulnerability and risk-taking in, including alcohol and drug use, mental health issues, low self esteem, homelessness and chaotic life style. Methodology Service provision was reviewed in comparison to the DoH standards. 50 sets of records were analysed. Results Reasons for attendance Contraception 80% PCC 60% Pregnancy Test 20% Sexual Screening 42% Recommendation: (1) development of integrated sexual health clinics, (2) PCT commissions a local, accessible abortion service, (3) develop links with other drug alcohol services, (4) combine sexual history sheet with the under 16s proforma, (5) Improve education about LARC in schools to promote uptake, (6) encourage a self-taken chlamydia swab or urine sample in those who decline full STI screening.

Background In 2006 BASHH guidelines for STI testing stated that there is no need to do a urethral smear in asymptomatic men. However there are concerns that this could result in delayed treatment of Chlamydia, or failure to diagnose an STI (eg, Mycoplasma genitalium ). Aims (1) To ascertain the female pathology associated with NGU. (2) To ascertain the number of women with significant pathology, (Chlamydia or PID) who attended only as a result of partner notification by a man with asymptomatic NGU. (3) To quantify the number of asymptomatic men who would have delayed treatment for chlamydia without immediate microscopy. Methods Note review of heterosexual males and their female contacts with NSU (100) and Chlamydia (50). Results 74% of 100 men treated for NSU were asymptomatic. Of these, 38 attended as a contact of infection and would have been treated anyway without microscopy. Of the remaining 36, 3 female partners had uncomplicated chlamydia and 3 PID but had not sought help for pelvic pain prior to their attendance in GUM. Overall, 70% of partners of men with NSU had significant pathology: Diagnoses in female partners of men with NSU Non-specific PID 35 Chlamydial PID 4 Uncomplicated Chlamydia 6 Non-specific cervicitis 9 Epidemiological treatment 46 of 50 men treated for Chlamydia 42% were asymptomatic. 28 (56%) had evidence of urethritis and a further 11 (22%) without pus on microscopy had noticeable threads in their urine. 47 attended prior to or with their partner, and 15 (30%) were treated at their initial visit due to immediate microscopy. These patients would have had to have been recalled for treatment. Conclusions In our cohort, 70% of female partners of men with NSU had significant pathology. 6/36 (17%) might not have been treated had they not attended as a contact of NSU. Microscopy can result in earlier treatment of asymptomatic men with Chlamydia due to immediate diagnosis of NGU, and may still be of value in GUM clinics.

Curved crystal spectrographs are described covering the range from potassium to uranium. With the higher speed model simultaneous recording of spectra between 0.5 to 2.5 ? or 1.5 to 3.75 ? is possible and minor constituents at the 0.1% level can be detected. A higher sensitivity version (down to 0.001%) employs a scanning device for covering the required wavelength range. With suitable comparison standards the instruments may be used for quantitative as well as qualitative analysis.

In comparing teleseismic P-wave delays in the vicinity of the Central Nevada Test Site in Hot Creek Valley, NV, with P-delay data over a wider region in the Great Basin, we found that upper mantle speeds under Hot Creek Valley stations are higher than the average for the Great Basin as a whole, but lower than those beneath Pahute Mesa. These observations indicate that the caldera complex in Hot Creek Valley may have a high speed root similar to that proposed to exist beneath the Silent Canyon caldera at Pahute Mesa. In constrast, the Hot Creek Valley anomaly is not as strong as the Pahute mesa anomaly. The shadow zone caused by the Pahute Mesa structure is much more pronounced and consequently magnitudes of Pahute mesa explosions can be underestimated relative to the magnitude of Hot Creek Valley explosions of similar yield. Spectral amplitudes for 24 events of the Mammoth Lakes earthquakes sequence have been determined for the frequency range 0.1-10.0 Hz, including the M sub L 6 earthquake at 1450 UT on May 27, 1980. We have found nothing in the spectra of this event nor in the spectra of the aftershocks to distinquish them from spectra of 'tectonic' earthquakes. However, the spectra themselves do not distinguish between various possible explanations for the non-double-couple source mechanism observed in moment tensor inversion and first motion data for the largest events of the Mammoth Lakes earthquake sequence. Journal reprints are included as appendices.

The microanalyser built at the R.A.R.D.E uses a modified Duncumb lens with six re-entrant ports. Geometric and spatial restrictions make it difficult to design a fully-focussing spectrometer of high efficiency for use with a lens of this type. Focussing spectrometers of limited range have been constructed [1] and a multi-crystal instrument is being built using focussing geometry on the specimen side only. This spectrometer however, like the semi-focussing instrument it will replace, requires a counter with a large window in order to intercept the whole of the diffracted beam at the higher values of θ, and the difficulty of making thin windows of sufficient strength increases with their physical size.

Bending and quenching methods for increasing the dislocation density and hence the X-ray reflection power of lithium fluoride have been found ineffective when applied to certain crystals of British origin. An ultrasonic treatment is described which, with abrasion of the surface, gave a gain in reflection intensity of up to 3½ times at 2.0 A and 7 times at 0.6 A.