Toward a unified interpretation of the “proper”/“smooth” orthogonal decompositions and “state variable”/“dynamic mode” decompositions with application to fluid dynamics

A common interpretation is presented for four powerful modal decomposition techniques: “proper orthogonal decomposition,” “smooth orthogonal decomposition,” “state-variable decomposition,” and “dynamic mode decomposition.” It is shown that, in certain cases, each technique can be interpreted as an optimization problem and similarities between methods are highlighted. By interpreting each technique as an optimization problem, significant insight is gained toward the physical properties of the identified modes. This insight is strengthened by being consistent with cross-multiple decomposition techniques. To illustrate this, an inter-method comparison of synthetic hypersonic boundary layer stability data is presented

Incidental Parasitic Infestations in Surgically Removed Appendices and its Association with Inflammation

Background:. To determine the frequency andtype of parasitic infestations in surgically removedappendices based on histopathological findings andto assess its association with inflammation.Methods: In this cross-sectional study 471appendices removed were included and theirhistopathologic examination reports were observed.In cases with parasitic infestations, informationregarding gender, age and presence of inflammationwas gathered. Fisher’s exact test at 5% level ofsignificance was applied to compare presence ofinflammatory infiltrates in appendices with andwithout parasites.Results: Of the 471 appendectomies performed, 15(3.18%) specimens were found to contain parasites,all of which were Enterobius vermicularis(pinworm). In those 15 cases, age of patients rangedfrom 9 to 45 years with a mean age of 19.07 ± 9.04years. Out of those 15 patients, 11 (73.3%) werefemales and 4 (26.7%) were males (male to femaleratio was 1:2.75). Only 2 out of 15 cases (13.3%) withparasitic infestation had inflammation, whereas in456 of the remaining non-parasitic appendices, 324(71.1%) were positive for inflammation. Thisdifference was statistically significant with a p value< 0.05.Conclusion: Frequency of parasitic infestations insurgically removed appendices is low. Very fewappendices with parasitic infestation are associatedwith inflammation as compared to appendiceswithout parasites

Psychological impact of COVID- 19 outbreak on health care professionals working at the Pakistan institute of medical sciences, Islamabad

Objective:  To assess anxiety and depression in healthcare professionals who are at high risk of exposure during the corona virus outbreak. Methodology: A cross-sectional descriptive study was performed from April 21, 2020 to June 21, 2020 at Pakistan Institute of Medical Sciences Islamabad. The number of healthcare professionals was selected using a simple random sampling technique from medicine and allied and surgical and allied. Standard SOPs were followed by both researchers and participants as per WHO and MOH guidelines.Self administered questionnaire in which anxious thoughts regarding Covid 19 were assessed. Reliable and validated research tools were used which included: a) Hospital Anxiety and Depression Scale (HAD-S), for evaluating level of anxiety and depression, b) Bradford Somatic Inventory (BSI), this assesses the somatic symptoms associated with anxiety and depression.Results: The study results on the Hospital Anxiety and Depression Scale indicate that overall, 76.47 % of the respondents showed the positive symptoms of anxiety. Among them 25.73% were males and 50.73% were females.  Overall, 4.65 % of respondents were facing depression, in which 2.69% pare females whereas 1.96 % were males. Scores on Bradford Somatic Inventory reveal that 0ut of 119 females 97 were found to have somatic symptoms, while out of 289 males 103 had somatic complaints. A total of 200 participants were found positive for somatic symptoms.Conclusion: It is concluded that there is a need for developing guidelines for healthcare professionals about effectively dealing in a health emergency situation like outbreak of this pandemic

Effects of Covid -19 on Mental Health of Positive Cases Compared with Suspected Cases

Objective: To assess and compare the effects of Covid 19 pandemics on mental health of diagnosed cases of corona virus with suspected cases and healthy subjects. Methodology: This comparative study  was conducted  at corona clinic of Pakistan Institute of Medical Sciences, and from April 2020 to Jun 2020. A total of 206 subjects were divided in three groups. Group-I (diagnosed as case of corona virus, n = 95), group-II (suspected cases n = 29) and group-III (healthy subjects, n = 82). They were matched for age, gender and socioeconomic status and were compared for frequency and severity of depression as measured by Hospital Anxiety and Depression Scale (HADS). Results: Some degree of depression was noted in all groups. Frequency of depression was 72.6% in group-I, 58.6% in group-II and 37.8% in group-III (p value < 0.001). Conclusion: Both diagnosed and people who came for screening (suspecting for Covid) had high frequency of some degree of anxiety and depression. Diagnosed patients had more anxiety and depressive features than suspected clients who came for screening. It is worthwhile to do more close mental health observation in them. This can be done by building up mental health interventions for improving their psychological wellbeing during the COVID-19 pandemic

Preliminary Study on Potentials of Pumice as the New Material for Floating Devices and Buoy Products

Pumice is a volcanic igneous rock which forms when magma with extremely high levels of water and gases is violently ejected from a volcano (in an explosive eruption), cools and depressurizes quickly and simultaneously above the ground. It is typically light colored, composed of volcanic glass, may or may not contain crystals, and commonly originated from high-silica (felsic) to intermediate magmas. Pumice commonly has vesicular or foamy (porous) texture and very low density, so it is enough for it to become the only rock that can float in water. In this study, pumice is for the first time exposed to see its potential as a new and alternative material to produce floating devices and buoy products. This rock is cut and shaped to become some products, such as surfing boards and lifebuoys. Different from other types of the same kind products that are mostly made of heavy materials, such as plastic (polyethylene), rubber, and fibreglass, pumice-based products are lighter, stronger, more buoyant, more durable, resistant, friendly to users and environmental as well as unique in appearance. Potential markets and customers of these products among others are sport and safety equipments traders and marine transportation (such as ship and ferry) companies. People can use pumice-based surfing boards personally for surfing activity and pumice-based lifebuoys for swimming especially for babies and kids

Memory Injections: Correcting Multi-Hop Reasoning Failures during Inference in Transformer-Based Language Models

Answering multi-hop reasoning questions requires retrieving and synthesizing information from diverse sources. Large Language Models (LLMs) struggle to perform such reasoning consistently. Here we propose an approach to pinpoint and rectify multi-hop reasoning failures through targeted memory injections on LLM attention heads. First, we analyze the per-layer activations of GPT-2 models in response to single and multi-hop prompts. We then propose a mechanism that allows users to inject pertinent prompt-specific information, which we refer to as "memories," at critical LLM locations during inference. By thus enabling the LLM to incorporate additional relevant information during inference, we enhance the quality of multi-hop prompt completions. We show empirically that a simple, efficient, and targeted memory injection into a key attention layer can often increase the probability of the desired next token in multi-hop tasks, by up to 424%

Attention Lens: A Tool for Mechanistically Interpreting the Attention Head Information Retrieval Mechanism

Transformer-based Large Language Models (LLMs) are the state-of-the-art for natural language tasks. Recent work has attempted to decode, by reverse engineering the role of linear layers, the internal mechanisms by which LLMs arrive at their final predictions for text completion tasks. Yet little is known about the specific role of attention heads in producing the final token prediction. We propose Attention Lens, a tool that enables researchers to translate the outputs of attention heads into vocabulary tokens via learned attention-head-specific transformations called lenses. Preliminary findings from our trained lenses indicate that attention heads play highly specialized roles in language models. The code for Attention Lens is available at github.com/msakarvadia/AttentionLens