We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Armed conflict and forced displacement can significantly strain nurturing family environments, which are essential for child well-being. Yet, limited evidence exists on the effectiveness of family-systemic interventions in these contexts. We conducted a two-arm, single-masked, feasibility Randomised Controlled Trial (fRCT) of a whole-family intervention with Syrian, Iraqi and Jordanian families in Jordan. We aimed to determine the feasibility of intervention and study procedures to inform a fully-powered RCT. Eligible families were randomised to receive the Nurturing Families intervention or enhanced usual care (1:1). Masked assessors measured outcomes at baseline and endline; primary outcome measures were caregiver psychological distress, family functioning, and parenting practices. Families and implementing staff participated in qualitative interviews at endline. Of the 62 families screened, 60 (98%) were eligible, 97% completed the baseline and 90% completed the endline. Qualitative feedback indicated specific improvements in adolescent well-being, caregiver distress and parenting, and family relationships. Data highlighted high participant engagement and adequate facilitator fidelity and competence. Outcome measures had good psychometric properties (most α > 0.80) and sensitivity to change, with significant changes seen on most measures in the intervention but not control group. Findings indicate the acceptability and feasibility of intervention and study procedures. Subsequent full-scale evaluation is needed to determine effectiveness.
A physically based computational model of drifting snow in two-dimensional terrain is developed. The model considers the case where wind speeds are low enough to neglect the transport of particles from the saltation layer into the turbulent flow field. The model has two distinct parts, one describing the turbulent airflow, and a second describing the mass-transport process and resulting snow-accumulation patterns produced by saltation transport. The turbulent-flow model consists of a general solution of the time-averaged, two-dimensional Navier-Stokes equations, where the k-∊ turbulence model is used to close the system of equations. The turbulent-flow model is coupled to a saltation model to compute the time evolution of the surface wind fields and snowdrift formation in the vicinity of a solid fence. Modeled wind fields and snow-accumulation profiles are similar to published field and experimental data.
After 21 years the Parkes radio telescope has undergone a major refit. A new VAX-11/750 running VMS has replaced the aged Digital Equipment Corporation PDP-9 computer. Other new equipment includes two systems not previously available — the Mk II RING communication system (Willing and Abies 1983) and the ‘observer workstations’.
Studies were made of visually and nonrvisitally guided movements by patients with Parkinson's disease. The subjects moved a light, horizontal handle using rotation primarily about the elbow. During visually guided trials both handle and target positions were displayed to the subject; during non-visually guided trials only the handle position was displayed. During non-visually guided trials all patients showed a tendency for an overall flexion drift, although there was no change in average movement amplitude. The overall error in position by the end of the non-visually guided trials was greatly in excess of the reported values for passive displacement thresholds in normal subjects. It is suggested that the data indicate an increased dependence on visual information for control of motor activity in Parkinson's patients.
Tarsal tunnel syndrome is a rare form of entrapment neuropathy. In athletes, it is usually the result of repetitive activity, local injury or a space-occupying lesion. Rarely, athletic footwear has been described as the primary cause of this syndrome.
Methods:
A 37-year-old male recreational hockey player was examined clinically and electrophysiologically because of spreading numbness in the toes of his left foot while playing hockey and wearing inflatable ice hockey skates designed to promote a better fit.
Results:
Clinical and electrophysiological studies revealed evidence of left medial and lateral plantar nerve involvement. Reduced amplitudes of mixed and motor plantar nerve responses with fibrillation potentials and positive sharp waves and no evidence of conduction block suggest that the primary pathology was axonal loss. Follow-up examination showed significant clinical and electrophysiological improvement after the patient stopped wearing his inflatable ice hockey skates.
Conclusion:
We report an unusual case of tarsal tunnel syndrome caused by an inflatable ice hockey skate. The patient improved clinically and electrophysiologically when he stopped wearing the boot.
Growth of larvae of the whitefringed weevil, Graphognathus leucoloma (Boheman), was studied in the laboratory and on various crops in pots in a shadehouse at Kairi, on the Atherton Tableland in north Queensland. In the laboratory at 25.5 ± 1°C there were 11 instars for which head capsule widths and weights were recorded. The first instar weighed 0.14 mg. This was a non-feeding stage capable of prolonged survival, and after 10 weeks in soil without food 60% survived. When provided with carrot (Daucus carota) larvae grew to 2 or 3 mg after 6 to 7 weeks, then increased rapidly in weight reaching 140 mg after 120 days. At 25.5°C the average time from first instar to adult was 311 days, due in part to a long prepupal period. Larval growth was measured on the roots of peanut (Arachis hypogaea) plants in pots in summer and winter. Under summer conditions (mean soil temperature 23.3°C) larvae reached 140 mg in about 120 days, similar to that in the laboratory on carrot. These fully grown larvae remained in the pots over the mild winter without pupating. Larvae developing in autumn/winter grew more slowly, but the fully grown larvae were then exposed to high spring (early summer) temperatures and soon pupated, the average time from first instar to adult being 273 days. The indications are that temperatures above 25°C quickly precondition mature larvae from Tolga for pupation, thus explaining the broad timing of adult emergence in the field in north Queensland. On different plants common near Tolga, larvae grew most quickly on peanuts and on the pasture legumes dolichos (Lablab purpureus) and stylosanthes (Stylosanthes guianensis). Survival on maize equalled that on peanuts (46.5% in sterilized soil) but growth was less. Larval survival and growth on the grass crowsfoot (Eleusine indica), and (surprisingly) on the pasture legume glycine (Neonotonia wightii) was very poor.
We are concerned with the stability properties of uniformly closed wedges in C(E) (resp. C+(E)), the real-valued (resp. non-negative) continuous functionson a compact space E, and solve the following problems in this area:
(a) Let A be a closed semi-algebra in C+(E) such that
A stimulus located outside the classic receptive field (CRF) of a striate cortical neuron can markedly influence its behavior. To study this phenomenon, we recorded from two cortical sites, recorded and peripheral, with separate electrodes in cats anesthetized with Propofol and nitrous oxide. The receptive fields of each site were discrete (2–7.3 deg between centers). A control orientation tuning (OT) curve was measured for a single recorded cell with a drifting grating. The OT curve was then remeasured while stimulating simultaneously the cell's CRF as well as the peripheral site with a stimulus optimized for that location. For 22/60 cells, the peripheral stimulus suppressed the peak response and/or shifted the center of mass of the OT curve. For 19 of these 22 cells, we then reversibly blocked stimulus-driven activity at the peripheral site by iontophoretic application of GABA (0.5 M). For 6/19 cells, the response returned to control levels, implying that for these cells the inhibitory influence arose from the blocked site. The responses of nine cells remained reduced during inactivation of the peripheral site, suggesting that influence was generated outside the region of local block in area 17. This is consistent with earlier findings suggesting that modulatory influences can originate from higher cortical areas. Three cells had mixed results, suggesting multiple origins of influence. The response of each cell returned to suppressed levels after dissipation of the GABA and returned to baseline values when the peripheral stimulus was removed. These findings support a cortical model in which a cell's response is modulated by an inhibitory network originating from beyond the receptive field that supplants convergence of excitatory lateral geniculate neurons.
An ultraviolet-specific (320-365 nm) digital camera based on a 128×128 array of backside-illuminated GaN/AlGaN p-i-n photodiodes has been successfully developed. The diode structure consists of a base n-type layer of AlGaN (~23% Al) followed by undoped and then p-type GaN layers deposited by metal organic vapor phase epitaxy. Double-side polished sapphire wafers serve as transparent substrates. Standard photolithographic, etching, and metallization procedures were employed to fabricate the devices. The fully-processed photodiode array was hybridized to a silicon readout integrated circuit (ROIC) using In bump bonds for electrical contact. The UV camera was operated at room temperature at frame rates ranging from 15 to 240 Hz. A variety of UV scenes were successfully recorded with this configuration.
A backside-illuminated solar-blind UV detector based on an AlGaN p-i-n heterostructure has been successfully synthesized, fabricated and tested. The p-i-n photodiode structure consists of a 1.0 μm n-type Al0.64Ga0.36N:Si layer grown by MOVPE onto a low temperature AlN buffer layer on a polished sapphire substrate. On top of this base layer is a 0.2 μm undoped Al0.47Ga0.53N active layer and a 0.5 μm p-type Al0.47Ga0.53N:Mg top layer. Square mesas of area A = 4 × 10−4 cm2 were obtained by reactive ion etching using BCl3. The solar-blind photodiode exhibits a very narrow UV spectral responsivity band peaked at 273 nm with a FWHM = 21 nm. Maximum responsivity R = 0.051 A/W at 273 nm, corresponding to an internal quantum efficiency of 27%. R0A values up to 8 × 107Ω-cm2 were obtained, corresponding to D* = 3.5 × 1012 cm Hz1/2W−1 at 273 nm.
Visible-blind UV cameras based on a 32 × 32 array of backside-illuminated GaN/AlGaN p-i-n photodiodes have been successfully demonstrated. The photodiode arrays were hybridized to silicon readout integrated circuits (ROICs) using In bump bonds. Output from the UV cameras were recorded at room temperature at frame rates of 30−240 Hz. These new visible-blind digital cameras are sensitive to radiation from 285−365 nm in the UV spectral region.
A visible-blind UV camera based on a 32 × 32 array of backside-illuminated GaN/AlGaN p-i-n photodiodes has been successfully demonstrated. Each of the 1024 photodiodes in the array consists of a base n-type layer of AlGaN (~20%) onto which an undoped GaN layer followed by a p-type GaN layer is deposited by metallorganic vapor phase epitaxy. Double-side polished sapphire wafers are used as transparent substrates. Standard photolithographic, etching, and metallization procedures were employed to obtain fully-processed devices. The photodiode array was hybridized to a silicon readout integrated circuit using In bump bonds. Output from the UV camera was recorded at room temperature at a frame rate of 30 Hz. This new type of visible-blind digital camera is sensitive to radiation from 320 nm to 365 nm in the UV spectral region.
Visible-blind UV cameras based on a 32 × 32 array of backside-illuminated GaN/AlGaN p-i-n photodiodes have been successfully demonstrated. The photodiode arrays were hybridized to silicon readout integrated circuits (ROICs) using In bump bonds. Output from the UV cameras were recorded at room temperature at frame rates of 30-240 Hz. These new visible-blind digital cameras are sensitive to radiation from 285-365 nm in the UV spectral region.
The epitaxial lateral overgrowth (ELO) process for GaN has been studied using SiC and sapphire substrates. Both MBE and MOVPE growth processes were employed in the study. The use of SiO2 versus SiNx insulator stripes was investigated using window/stripe widths ranging from 20 μm/4 μm to 3 μm/15 μm. GaN film depositions were completed at temperatures ranging from 800 °C to 1120 °C. Characterization experiments included RHEED, TEM, SEM and cathodolumenescence studies. The MBE growth experiments produced polycrystalline GaN over the insulator stripes even at deposition temperatures as high as 990 °C. In contrast, MOVPE growth produced single-crystal GaN stripes with no observable threading dislocations.
A systematic study of the growth and doping of GaN, AlGaN, and InGaN by both molecular beam epitaxy (MBE) and metal-organic vapor phase epitaxy (MOVPE) has been performed. Critical differences between the resulting epitaxy are observed in the p-type doping using magnesium as the acceptor species. MBE growth, using rf-plasma sources to generate the active nitrogen species for growth, has been used for III-Nitride compounds doped either n-type with silicon or p-type with magnesium. Blue and violet light emitting diode (LED) test structures were fabricated. These vertical devices required a relatively high forward current and exhibited high leakage currents. This behavior was attributed to parallel shorting mechanisms along the dislocations in MBE grown layers. For comparison, similar devices were fabricated using a single wafer vertical flow MOVPE reactor and ammonia as the active nitrogen species. MOVPE grown blue LEDs exhibited excellent forward device characteristics and a high reverse breakdown voltage. We feel that the excess hydrogen, which is present on the GaN surface due to the dissociation of ammonia in MOVPE, acts to passivate the dislocations and eliminate parallel shorting for vertical device structures. These findings support the widespread acceptance of MOVPE, rather than MBE, as the epitaxial growth technique of choice for III-V nitride materials used in vertical transport bipolar devices for optoelectronic applications.
Information on the responses in meat and eating quality to selection for components of lean growth rate is important to the British pig breeding industry when evaluating alternative selection strategies. The current study determined responses in meat and eating quality traits to selection for components of lean growth rate.
Knowledge of the genetic and phenotypic relationships for muscle fibre characteristics with meat and eating quality in pigs is required by the pig breeding industry for two reasons. Muscle fibre traits, determined from muscle biopsy, could be used as genetic predictors of meat and eating quality traits and, secondly, if responses in meat and eating quality traits are partially due to changes in muscle fibre traits, then selection criteria can be designed to compensate for such responses. The current study estimated the genetic and phenotypic relationships for muscle fibre traits with meat and eating quality traits.
The study consisted of 160 Large White pigs from lines divergently selected for lean growth rate on ad-libitum or restricted feeding regimes, lean food conversion ratio and daily food intake for seven generations in the Edinburgh lean growth selection experiment. Within each selection line, there were 10 pairs of full-sibs. Boars and gilts were tested from 30 kg, individually penned and fed a diet consisting of 224 g CP/kg DM and 15.9 MJ DE/kg DM.