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Approximate analytic expressions for the transmitted and diffracted fields from a non-uniform in-fiber Bragg grating are presented, in terms of Hermite and Kummer confluent hypergeometric functions. These novel approximate analytic solutions are derived for the case of a grating having both a weak linear variation of grating period with length (weak linear chirp) and a quadratic approximation to a Gaussian refractive index modulation variation. The solution is derived using the Beta-value first-order two-wave coupled differential equations and describes both on- and off-Bragg replay. The equations are shown to be useful, when compared to more exact numerical results, for a wide range of practical grating parameter values.

For paraxial wave-fields in two dimensions, it is known that the defocused OTF is given by a section through the ambiguity function. This is no longer true for high aperture fields. It is shown that there is a simple relationship, even for high aperture fields, between the two-dimensional (one transverse and one longitudinal) generalized OTF and the spectral correlation function. The connection with the Wigner distribution function is also discussed. The generalization to three-dimensional wavefields is also considered.

Forty-two patients (45 fingers) were retrospectively reviewed after operative release of flexion contractures of the proximal interphalangeal (PIP) joint. The release was accomplished through a palmar incision in 19 fingers, usually followed by skin coverage using a lateral transposition flap. A midlateral incision was used in 26 fingers. The 2 groups were comparably matched with respect to degree of contracture and demographic characteristics. Active range of motion (ROM) was measured before and after surgery. In the palmar incision group, preoperative median PIP joint ROM was 60 degrees to 90 degrees (extension/flexion) and 30 degrees to 90 degrees at the 3-year follow-up examination. In the midlateral incision group, preoperative median PIP joint ROM was 50 degrees to 90 degrees (extension/flexion) and 0 degrees to 90 degrees at the 1.5-year follow-up examination. The improvement in ROM was significantly better in the midlateral incision group than in the palmar incision group.

The significance of the similarity theorem for the fractional Fourier transform is discussed, and the properties of self-similar functions considered. The concept of the fractional Hankel transform is developed for use in the analysis of diffraction and imaging in symmetrical optical systems. The particular case of Fresnel diffraction from a circular aperture is discussed and the effects of the similarity theorem are described.

At present the best methods for rotation of discrete sampled images use a combination of (fast) Fourier interpolation followed by cubic interpolation onto a rotated grid. A method is presented which uses only Fourier interpolation. The new method has a similar computational complexity to the old, and is exactly reversible. The method uses the well-known decomposition of rotation into three pure shears. Each shear is performed using a 2D extension of the 1D Fourier shift theorem. This allows the fast Fourier transform (FFT) to be used. With appropriate data padding (such as zero padding) in both the real and Fourier domains, the procedure gives near perfect results and minimal loss of information in multiple rotation tests.

Summary In an imaging system, it is known that the information capacity, rather than the resolution, is invariant. Thus super-resolution can be achieved by encoding/decoding additional information on to independent parameters of the imaging system. The concept of information capacity is extended to the full three-dimensional case.

Tolerance to the effects of benzodiazepines (BZ) may be mediated by changes in benzodiazepine receptors (BZRs). Peripheral BZRs (in brain and platelets) and central BZRs (in brain) were measured in rats following intraperitoneal administration of diazepam and clobazam each for 4 and 12 days. BZRs were measured by binding assays using [3H] PK 11195 (peripheral) and [3H] flunitrazepam (central) as radioligands. Diazepam, but not clobazam, increased peripheral BZR numbers in platelets (both P < 0.005), but not in brain, after 4 and 12 days' treatment compared with appropriate controls. Neither drug altered central BZR affinities or numbers in rat brain. BZ effects on peripheral BZRs in platelets cannot be extrapolated to predict changes in brain receptors, either peripheral or central.

Twenty-two patients (8 male, 14 female) with refractory epilepsy entered a balanced, double-blind, placebo-controlled crossover trial of nimodipine as adjunctive therapy. Treatment periods of 12 weeks (nimodipine 30 mg tds, 60 mg tds, 90 mg tds each for 4 weeks and matched placebo) were followed by wash-out intervals of 4 weeks. Five patients withdrew (2 side-effects, 1 intercurrent illness, 2 non-compliance). Median values (placebo vs. nimodipine) did not vary for total (17 vs. 18), partial (14 vs. 18) and generalised tonic-clonic seizures (2 vs. 5) or seizure days (13 vs. 13). Monthly analysis also failed to uncover any benefit for nimodipine. Side-effects were reported no more frequently with nimodipine than with placebo and pulse and blood pressure did not alter significantly. Antiepileptic drug levels were not affected by nimodipine treatment but circulating nimodipine concentrations were low. In this trial, nimodipine did not fulfil the promise of its success in animal models of epilepsy. Enzyme induction by concurrent antiepileptic therapy may provide an explanation.

A battery of psychometric tests was administered to 102 adult patients with epilepsy. Forty-eight were receiving long-term treatment with sodium valproate (VPA) as monotherapy, and 28 took a combination of VPA with either carbamazepine or phenytoin. An additional 26 patients were untreated, and the tests were also administered to 24 nonepileptic controls. The polypharmacy group performed significantly less well than the other groups in 6 of the 11 tests. Overall, there were no differences in performance between the VPA monotherapy patients and both the drug-free groups. However, patients with higher total and free VPA concentrations reported more sedation and scored less well on the threshold detection task. Patients were divided into those “tolerant” and “intolerant” to the drug in terms of these two tests. The “intolerant” group had a significantly earlier age of onset of epilepsy and a lower nonverbal IQ. Monotherapy with VPA is unlikely to impair cognitive function and may be a suitable choice if cognitive function is an important consideration.

A battery of psychometric tests was administered to 110 patients with epilepsy and to 24 non-epileptic controls. Eighty-four patients had been established on treatment with a single anticonvulsant drug (35 carbamazepine (CBZ), 30 sodium valproate (VPA), 19 phenytoin (PHT)) at unaltered dosage for the previous 3 months. The remaining 26 patients were untreated at the time of study. No individual test discriminated between the groups. Tests were converted to standard scores and summated to give overall psychomotor, memory and side-effect assessments. There were no important differences between the performances of untreated epileptic patients and non-epileptic controls. The CBZ-treated patients had poorer psychomotor scores than both control groups and the VPA-treated patients (all P less than 0.05). The PHT patients scored less well on the composite memory scale than did VPA patients and non-epileptic controls (both P less than 0.05). There were no significant differences in subjective side-effects among the groups. This study demonstrated that anticonvulsant monotherapy has little effect on overall cognitive function in patients tolerating treatment. Psychomotor performance appeared to be selectively influenced by CBZ and memory impaired by PHT. VPA may be the drug to chose when cognitive function is an important consideration. Different cognitive modalities can be affected by different first-line anticonvulsants and this should be taken into account when choosing the most appropriate drug for an individual patient.

Purpose The purpose of this study was to examine spirituality as a meaningful construct in adolescents' lives, and to examine the contribution of spirituality above and beyond that of religiosity to depressive symptoms and health-risk behaviors. Methods A total of 134 adolescents from a suburban high school completed a questionnaire assessing spirituality, religiosity, depressive symptoms, and health-risk behaviors. Spirituality was measured with 2 subscales: (1) religious well-being ("I believe that God loves/cares about me") and (2) existential well-being ("Life doesn't have much meaning"). Religiosity was assessed via belief in God/Higher Power and importance of religion. The Children's Depression Inventory-Short Form and the Youth Risk Behavior Survey (YRBS) were used to assess depressive symptoms and health-risk behaviors. Results The majority of the sample was Caucasian, with a mean age of 16.2 years. Eighty-nine percent reported a belief in God/Higher Power and 77% stated that religion was important in their lives. After controlling for demographics and religiosity, existential well-being and religious well-being accounted for an additional 29% of the variability in depressive symptoms and 17% of the variability in risk behaviors. Existential well-being was the only predictor significant in both final models ( p Conclusions Most of these adolescents reported some connection with religious and spiritual concepts, and those with higher levels of spiritual well-being, in particular, existential well-being, had fewer depressive symptoms and fewer risk-taking behaviors. This supports the inclusion of these concepts in our efforts to help promote resilience and healthy adolescent development, and in expanding our investigations beyond religious identification or attendance at religious services to broader concepts of spirituality.