Towards optimal multimode fiber imaging by leveraging input polarization and conditional generative adversarial networks

Deep learning techniques provide a plausible route towards achieving practical imaging through multimode fibers. However, the results produced by these methods are often influenced by physical factors like temperature, fiber length, external perturbations, and polarization state of the input light. The impact of other factors, except input light polarization, has been discussed in the literature for imaging applications. The input polarization has been considered by researchers while looking at the characterization and control of polarization in multimode fibers. Here, we show experimentally that the state of polarization of light, being injected at multimode fiber input, affects the fidelity of reconstructed images from speckle patterns. Certain polarization states produce high-quality images at fiber output, while some yield degraded results. We have designed a conditional generative adversarial network~(CGAN) for image regeneration at various degrees of input light polarization. We demonstrate that in the case of multimode fibers that are held fixed, optimal imaging can be achieved by leveraging our CGAN model with the input light polarization state, where the fidelity of images is maximum. Our work exhibits high average structural similarity index values exceeding 0.9, surpassing the previously reported value of 0.8772. We also show that the model can be generalized to image adequately for all input light polarization states when the fiber has bends or twists. We anticipate our work will be a stepping stone toward developing high-resolution and less invasive multimode fiber endoscopes

Angioembolization in itractable epistaxis—a tertiary care experience

Objective: To review the role of angioembolization in the control of intractable epistaxis at our institution. Methods: A retrospective review of the charts of the patients between Jan 2001 to June 2010 at Aga Khan University Hospital, Karachi was done. All patients who underwent angioembolization for intractable epistaxis were included in the study. Patients with nasal or nasopharyngeal mass were excluded. Data was analyzed by using SPSS version 16. Results: Total numbers of the patients were 16. Fourteen (87.5%) patients were male and 2(12.5%) were female with mean age 51.2 ± 12.922 years (range 26-71 years). In 11(68.75%) patients there were no associated risk factors for epistaxis, 3(18.75%) patients had uncontrolled hypertension, 1(6.25%) patient had road traffic accident and 1(6.25%) patient had bleeding after nasal surgery. All patients were initially treated by anterior and posterior nasal packing for 48 to 72 hours. Angioembolization successfully controlled epistaxis in all 16 (100%) patients initially. However, in 2(12.5%) cases embolization had to be repeated; in 1 patient on the same day and in another patient after one month of initial procedure. The average length of stay after angioembolization was 1.9 ± 0.854 days. No major or permanent complication was observed. Two (12.5%) patients developed minor complications (1 patient experienced facial pain for 7 days and another patient developed haematoma at the site of femoral artery). Conclusion: Angioembolization is a safe and effective treatment option for intractable epistaxi

The rationality of prescribing antibiotics after tonsillectomy

Objective: To compare the antibiotic therapy with the absence of antibiotic therapy in reducing post-tonsillectomy morbiditiesMethods: The quasi-experimental study was conducted at the Aga Khan University Hospital, Karachi, from November 2006 to September 2007. It involved 60 patients fulfilling the criteria for recurrent tonsillitis who were divided in two groups based on the different practice of two sets of surgeons. In one group antibiotics were used, while in the other group, no antibiotic was given. Patients filled a questionnaire about pain, post-operative bleeding, day of normal diet intake, day of normal activity and any consultation received during the first post-operative week. The data collected was analyzed using SPSS version 16.Results: There were 60 patients who were divided in two groups of 30 each on the basis of purposive sampling technique. Mean age was 21.43 ± 8.3 years. Of the total, 55% were male and 45% were female. Post-operative pain was comparable between the two groups. Four patients had secondary haemorrhage - three in the antibiotic group, and one in the non-antibiotic group. Mean day of normal activities and normal diet intake was almost the same in both groups. Unscheduled hospital visits were 6.9% in the antibiotic group, and 3.3% in the non-antibiotic group.Conclusion: The study showed that antibiotics did not have any significant impact in reducing the post-tonsillectomy morbidities

Personalizing Task-oriented Dialog Systems via Zero-shot Generalizable Reward Function

Task-oriented dialog systems enable users to accomplish tasks using natural language. State-of-the-art systems respond to users in the same way regardless of their personalities, although personalizing dialogues can lead to higher levels of adoption and better user experiences. Building personalized dialog systems is an important, yet challenging endeavor and only a handful of works took on the challenge. Most existing works rely on supervised learning approaches and require laborious and expensive labeled training data for each user profile. Additionally, collecting and labeling data for each user profile is virtually impossible. In this work, we propose a novel framework, P-ToD, to personalize task-oriented dialog systems capable of adapting to a wide range of user profiles in an unsupervised fashion using a zero-shot generalizable reward function. P-ToD uses a pre-trained GPT-2 as a backbone model and works in three phases. Phase one performs task-specific training. Phase two kicks off unsupervised personalization by leveraging the proximal policy optimization algorithm that performs policy gradients guided by the zero-shot generalizable reward function. Our novel reward function can quantify the quality of the generated responses even for unseen profiles. The optional final phase fine-tunes the personalized model using a few labeled training examples. We conduct extensive experimental analysis using the personalized bAbI dialogue benchmark for five tasks and up to 180 diverse user profiles. The experimental results demonstrate that P-ToD, even when it had access to zero labeled examples, outperforms state-of-the-art supervised personalization models and achieves competitive performance on BLEU and ROUGE metrics when compared to a strong fully-supervised GPT-2 baselineComment: 11 pages, 4 tables, 31st ACM International Conference on Information and Knowledge Management (CIKM'22

Distribution of Helminth Parasites in Intestines and Their Seasonal Rate of Infestation in Three Freshwater Fishes of Kashmir

The present study was undertaken to determine the incidence of helminth parasites in fishes with special reference to water quality parameters in Dal Lake and River Jhelum and correlate the observations. Water, fish, and parasite samples were collected during different seasons from various sites and processed. Three fish species, namely, Schizothorax niger Heckel 1838, Schizothorax esocinus Heckel 1838, and Schizothorax curvifrons Heckel 1838, were recovered from these water bodies. The physicochemical parameters temperature, dissolved oxygen, pH, and free carbon dioxide showed variation vis-à-vis the season and location of the stations in water bodies. Acanthocephalan parasite Pomphorhynchus kashmirensis Kaw 1941 (27.47%) and two intestinal cestodes Bothriocephalus acheilognathi Yamaguti 1934 (30.63%) and Adenoscolex oreini Fotedar 1958 (32.43%) were recovered from all the three species of Schizothorax. All the three parasites showed higher prevalence during summer and the least prevalence during winter. Parasitic infections were prevalent more in male fishes compared to females. The presence of the parasites had reduced the condition coefficient of the infected fishes in both water bodies. The study also showed that some of the physicochemical features showed a significant positive correlation with the prevalence

Practice of standard Cross Infection Protocol in Private Dental Clinics of Khyber Pakhtunkhwa, Pakistan: A cross-sectional study

Background: Infection control, which is considered to be the backbone of dentistry, has become a particularly essential piece of dental training because both the dentists and patients are at an expanded danger of cross-contamination. Dental clinical settings represent a high organic hazard of spreading a wide scope of microorganisms. The objective of this study is to gather information of different dentists regarding their practice of standard cross infection protocols and how can they improve the same in their private practices. Materials and Methods: This cross-sectional study was conducted in dental clinics of Khyber Pakhtunkhwa, KPK from January 2020 to July 2020 by distributing a questionnaire among dentists. It was a pre-designed questionnaire that was circulated in Google forms through Whatsapp and emails. The questionnaire was divided into 2 sections. Data was compiled and statistical tests were applied using the Statistical Package for Social Sciences SPSS® ver.23.0 Results: Regarding cross infection control measures, maximum dentists seem to have knowledge of cross infection control techniques. A significant difference was found (p= 0.05) between male & female dentists in disposing dental waste from clinical set up properly. A significant difference was also found between male & female dentists about rubber dam isolation (p=0.02). Conclusion: The result of this study showed that practice of dentists in KPK is not up to standard protocols of cross infection control. In this way, the need of great importance is to authorize and execute better proportions of infection control to improve dental practice in KPK. Key words: Infection control, Dental practice, Sterilizatio

Hepatoprotective effect of Cichorium Intybus linn (Kasni) Extracts against Carbon Tetrachloride induced Liver Damage

Background: To assess the effect of aqueous and alcoholic extracts of Cichorium intybus linn , frequently used by Hakims and traditional healers, on liver, against the carbon tetrachloride (CCl4) induced hepatic injury. Methods: In this experimental intervention study, forty rats were subdivided into four sub groups, ten in each group. Group I was kept as standard control. For this study three groups (II, III, IV) were made in which aqueous and alcoholic extract was given prior to hepatic damage by CCl4. Hepatoprotective effect was assessed by measuring serum levels of alanine transaminase(ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP). Results: Very significant hepatoprotective effect (p<0.001) was observed by alcoholic extract while aqueous extract showed no significant effect against CCl4 induced hepatic injury. Conclusion: Alcoholic extract of Cichorium intybus linn exhibits a very significant hepatoprotective effec

Perioperative hemodynamic effects of dexmedetomidine as an adjuvant to 0.2% ropivacaine in ultrasonography guided interscalene brachial plexus block for elective shoulder arthroscopic surgeries under general anaesthesia: a prospective observational study

Background: Although an increasing number of anesthesiologists are using peripheral nerve catheters for postoperative analgesia, single shot blocks are still more common. Ropivacaine has become the most commonly used long-acting local anesthetic, and the duration of analgesia has been estimated to be 8 to 14 hours.Methods: The study was conducted from February 2020 to October 2021 after obtaining approval from the institutional ethics committee. The study was a prospective observational study.Results: Hemodynamic changes in patients who received dexmedetomidine in combination with Ropivacaine had a favorable reduction in both heart rate and blood pressure without causing any major side effect. Comparison of postoperative MAP (mmHg) in two groups at various intervals of time was observed and found to be statistically significant (p value of <0.05). Comparison of postoperative heart rate (beats/min) among two groups at various intervals of time was statistically significant (p value of <0.05).Conclusions: We can conclude that preoperative inter-scalene block given reduces the analgesic requirement intraoperatively as well postoperatively. And the hemodynamic changes in patients who received dexmedetomidine in combination with ropivacaine had a favorable reduction in both heart rate and blood pressure without causing any major side effect.

Antagonistic States in Multilateral Forums: India and Pakistan in SAARC and SCO

This research paper examines India and Pakistan's divergent behavior displayed within two regional organizations, namely the South Asian Association for Regional Cooperation (SAARC) and the Shanghai Cooperation Organization (SCO). Despite their longstanding animosity, both countries actively participated in SCO summits while demonstrating reluctance to engage with each other within SAARC since 2019. By investigating the underlying reasons for this divergent behavior, we analyze the implications for SCO in the context of the Indo-Pak arch rivalry. Employing game theory, precisely the prisoner's dilemma, we examine the dynamics of cooperation and conflict. Through this analysis, we uncover the distinctive functioning of multilateralism within SAARC and SCO, providing insights into the influence of India-Pakistan relations on these regional institutions. The findings of this study enhance our comprehension of the complexities surrounding multilateral cooperation and the significant role arch rivalry plays in shaping regional dynamics