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Cryogenic treatment of polymers is a well-known area of research these days. Many reports confirm the fact that, similar to metals, polymeric materials also undergo some structural changes that ultimately enhance mechanical properties like wear performance, tensile strength, impact strength, elongation, hardness, etc. The cryogenic treatment has proven an advantage for improving the properties of both virgin polymers and polymer micro- and nanocomposites. The present study, the first of its kind, reports the effect of cryogenic treatment on polymeric blends. An attempt is made to explore the effect of the treatment parameters, like temperature and time, on the impact modified and unmodified PET/PBT blends. Similar to the polymers and composites, the blend systems studied here reflect significant improvement by ∼50% in wear performance, ∼16–19% in tensile strength, and ∼9% in impact strength after cryogenic treatment. Thus, after extensive analysis of the material properties, structure, and thermal behavior, cryogenic treatment of PET/PBT blends, both impact-modified and unmodified, is advocated as an effective tool for tailoring the interface and improving performance.

Background Stress urinary incontinence (SUI) is a common problem affecting the quality of life of women. Materials and Methods It is a prospective study conducted over 40 women of SUI by endovaginal ultrasound on rest and Valsalva preoperatively and 6 months postoperatively for levator hiatus (LH), pubovisceral thickness, urethral length, and bladder neck (BN) position. A 24 h pad test was also performed on all women at the same time for grading of SUI. Treatment given was medical in 4 (10%), Burch colposuspension in 18 (45%), and tension-free obturator tape in 18 (45%). Results The mean age, parity, and body mass index in the study were 41.60 years, 2.73, and 24.2 kg/m2, respectively. All 40 (100%) patients had SUI with a mean duration of symptoms being 4.04 years. On 24 h pad test, mild SUI was in 4 (10%), moderate SUI in 33 (82.5%), and severe SUI in 3 (7.5%) with mean preoperative 24 h pad test being 36.69 g which significantly reduced to 9.79 g postoperatively (P = 0.001). There was significant change in LH and pubovisceral thickness with treatment of SUI. Overall urethral length increased but there was significant decrease in urethral length on Valsalva after the treatment (0.40 cm vs. 0.28 cm, P = 0.04) and significant reduction in BN descent after Valsalva after treatment (0.41 cm vs. 0.27 cm, P = 0.001). Conclusion Endovaginal ultrasound and 24 h pad test are the useful diagnostic modalities for SUI diagnosis and to see the impact of treatment.

Background: Stress urinary incontinence (SUI) is a common ailment in affecting quality of life. This study was performed to see role of incontinence severity index (ISI) in evaluating severity of SUI and to see the impact of treatment of SUI. Materials and Methods: A total of 40 women with the diagnosis of SUI on history and clinical examination were enrolled. ISI was calculated on all the women before treatment. All women were treated with either conservative treatment (pelvic floor exercises, life style modification, and duloxetine therapy) (4, 10%) or Burch's colposuspension (18, 45%) or tension-free obturator tape (18, 45%) as per clinical situation after discussion with patients. ISI was again calculated 6 months after treatment. Results: Mean age, parity, body mass index in the study were 41.60 years, 2.73, and 24.2 kg/m2, respectively. All 40 (100%) patients had SUI with the mean duration of symptoms being 4.04 years. A total of 11 (27.5%) had moderate SUI (ISI 3–6), while 24 (60%) had severe SUI (ISI 8–9), while 5 (12.5%) had very severe SUI (ISI 12). Range of pretreatment ISI was 3–12 with mean being 8.8 ± 3.2. Posttreatment ISI reduced significantly with range of 1–4 and mean of 1.3 ± 0.4 (P < 0.001). The reduction was significant for all the groups, but there was no significant difference in efficacy of three treatment groups. Statistical analysis was done using SPSS IBM Version 2-1-0 using Chi-square test, Fisher's Extract test, and ANOVA test as appropriate. Conclusion: ISI is a useful modality to evaluate the severity of SUI and to see the impact of treatment modalities on SUI.

Centistidea acrocercopsi Ahmad & Pandey, sp. nov., C. cosmopteryxi Ahmad & Pandey, sp. nov., and C. tihamica Ghramh & Ahmad, sp. nov. are described as new to science. The genus Centistidea Rohwer (Hymenoptera: Braconidae: Miracinae) is recorded for the first time from Saudi Arabia. Two species were reared from Acrocercops phaeospora Meyrick and Cosmopteryx phaeogastra (Meyrick) in India, while Centistidea tihamica was collected by Malaise trap in Saudi Arabia. Characters of these new species and their affinities with related taxa are discussed. Data on habitat, host records, and host plant species for all the parasitoid species are also provided.

Pholetesor acrocercophagus sp. nov., P. camerariae sp. nov. and P. indicus sp. nov.(Hymenoptera: Braconidae: Microgastrinae) are described as new to science. These three species were reared from Acrocercops sp., Acrocercops phaeospora Meyrick, 1916 and Cameraria virgulata Meyrick, 1914 (Lepidoptera: Gracillariidae), respectively. Characteristics of these new species and their affinities with related taxa are discussed. Data on habitat, host records and host plant species for all the parasitoid species is provided. A key to the Indian species of the genus Pholetesor Mason, 1981 reared from lepidopteran leafminers is also given.

This paper investigates the effect of ageing on the performance of dye-sensitized solar cells (DSCs). The electrical characterization of fresh and degraded DSCs is done under AM1.5G spectrum and the current density-voltage (J-V) characteristics are analyzed. Short circuit current density (JSC) decreases significantly whereas a noticeable increase in open circuit voltage is observed. These results have been further investigated electroanalytically using electrochemical impedance spectroscopy (EIS). An increase in net resistance results in a lower JSC for the degraded DSC. This decrease in current is mainly due to degradation of TiO2-dye interface, which is observed from light and dark J-V characteristics and is further confirmed by EIS measurements. A reduction in the chemical capacitance of the degraded DSC is observed, which is responsible for the shifting of Fermi level with respect to conduction band edge that further results in an increase of open circuit voltage for the degraded DSC. It is also confirmed from EIS that the degradation leads to a better contact formation between the electrolyte and Pt electrode, which improves the fill factor of the DSC. But the recombination throughout the DSC is found to increase along with degradation. This study suggests that the DSC should be used under low illumination conditions and around room temperature for a longer life.