167 research outputs found
Choices and Consequences: A Cross-National Evaluation of Telecommunication Policies in Developing Countries
Telecommunications are increasingly being recognized as critical strategic infrastructure for ensuring the success of national social and economic development plans and programs, improving international competitiveness and integrating domestic economies into the world economy. In an effort to overcome chronic deficiencies in telecommunication performance and distribution of services, many developing countries have been engaged in liberalizing their telecommunication sectors. Liberalization here referring to the movement away from the traditional state-owned monopoly structure and towards the introduction of privatization and competition. This study examines the consequences of these developments by analyzing telecommunication developments in 81 developing countries from 1977 to 1988. The study is in two parts. The first part is theoretical and (a) identifies the technological and economic forces driving change in the sector; (b) reviews the policy options available to developing countries; (c) critically discusses the arguments both for and against the introduction of competition and privatization in the sector; and (d) outlines the importance of governmental commitment to the growth of telecommunications. The second part is empirical and presents the findings of a cross-national longitudinal evaluation of the impact of changes in policies governing sector structure for the supply and manufacture of telecommunications equipment, facilities and services, as well as the impact of governmental commitment, on sector performance and distribution. The evaluation is conducted in the context of the economic factors which are thought to condition the relationship between telecommunication policies and outcomes. It finds that movement toward liberalization has had little independent impact on telecommunications sector performance, but is associated with adverse conditions of access to and availability of services. In contrast, governmental commitment to the growth of the sector is found to be positively related with improvements in both sector performance and distribution at all levels of national income and under different compositions of economic activity. The findings suggest that if sector growth and development are important national priorities then attention should be turned more toward stepping-up government investments rather than towards sector restructuring
Online Discrepancy Minimization for Stochastic Arrivals
In the stochastic online vector balancing problem, vectors
chosen independently from an arbitrary distribution in
arrive one-by-one and must be immediately given a sign.
The goal is to keep the norm of the discrepancy vector, i.e., the signed
prefix-sum, as small as possible for a given target norm.
We consider some of the most well-known problems in discrepancy theory in the
above online stochastic setting, and give algorithms that match the known
offline bounds up to factors. This substantially
generalizes and improves upon the previous results of Bansal, Jiang, Singla,
and Sinha (STOC' 20). In particular, for the Koml\'{o}s problem where
for each , our algorithm achieves
discrepancy with high probability, improving upon the previous
bound. For Tusn\'{a}dy's problem of minimizing the
discrepancy of axis-aligned boxes, we obtain an bound for
arbitrary distribution over points. Previous techniques only worked for product
distributions and gave a weaker bound. We also consider the
Banaszczyk setting, where given a symmetric convex body with Gaussian
measure at least , our algorithm achieves discrepancy with
respect to the norm given by for input distributions with sub-exponential
tails.
Our key idea is to introduce a potential that also enforces constraints on
how the discrepancy vector evolves, allowing us to maintain certain
anti-concentration properties. For the Banaszczyk setting, we further enhance
this potential by combining it with ideas from generic chaining. Finally, we
also extend these results to the setting of online multi-color discrepancy
Prefix Discrepancy, Smoothed Analysis, and Combinatorial Vector Balancing
A well-known result of Banaszczyk in discrepancy theory concerns the prefix
discrepancy problem (also known as the signed series problem): given a sequence
of unit vectors in , find signs for each of them such
that the signed sum vector along any prefix has a small -norm?
This problem is central to proving upper bounds for the Steinitz problem, and
the popular Koml\'os problem is a special case where one is only concerned with
the final signed sum vector instead of all prefixes. Banaszczyk gave an
bound for the prefix discrepancy problem. We
investigate the tightness of Banaszczyk's bound and consider natural
generalizations of prefix discrepancy:
We first consider a smoothed analysis setting, where a small amount of
additive noise perturbs the input vectors. We show an exponential improvement
in compared to Banaszczyk's bound. Using a primal-dual approach and a
careful chaining argument, we show that one can achieve a bound of
with high probability in the smoothed setting.
Moreover, this smoothed analysis bound is the best possible without further
improvement on Banaszczyk's bound in the worst case.
We also introduce a generalization of the prefix discrepancy problem where
the discrepancy constraints correspond to paths on a DAG on vertices. We
show that an analog of Banaszczyk's bound continues
to hold in this setting for adversarially given unit vectors and that the
factor is unavoidable for DAGs. We also show that the
dependence on cannot be improved significantly in the smoothed case for
DAGs.
We conclude by exploring a more general notion of vector balancing, which we
call combinatorial vector balancing. We obtain near-optimal bounds in this
setting, up to poly-logarithmic factors.Comment: 22 pages. Appear in ITCS 202
Xanthogranulomatous Endometritis with calculus formation in setting of prolapsed uterus
Xanthogranulomatous inflammation is a rare benign inflammatory lesion characterized by sheets of lipid-laden foamy histiocytes. It has been reported in various organs, mainly the kidney and gall bladder. Xanthogranulomatous endometritis (XGE) is sporadic, with only a few cases reported in the English medical literature. Herein, we report a case of xanthogranulomatous endometritis with the formation of stones in a 50-year-old female patient with a prolapsed uterus. Grossly the endometrium was irregular, and the uterine cavity was filled with a yellow friable material, a polypoid growth, and yellowish stones. The microscopy showed sheets of histiocytes with few preserved endometrial glands. In this case, the xanthogranulomatous inflammation may mimic a clear cell carcinoma involving the endometrium and myometrium. One of the important differential diagnoses is malakoplakia. Immunohistochemistry and special stains are helpful in diagnosis
Surveys without Questions: A Reinforcement Learning Approach
The 'old world' instrument, survey, remains a tool of choice for firms to
obtain ratings of satisfaction and experience that customers realize while
interacting online with firms. While avenues for survey have evolved from
emails and links to pop-ups while browsing, the deficiencies persist. These
include - reliance on ratings of very few respondents to infer about all
customers' online interactions; failing to capture a customer's interactions
over time since the rating is a one-time snapshot; and inability to tie back
customers' ratings to specific interactions because ratings provided relate to
all interactions. To overcome these deficiencies we extract proxy ratings from
clickstream data, typically collected for every customer's online interactions,
by developing an approach based on Reinforcement Learning (RL). We introduce a
new way to interpret values generated by the value function of RL, as proxy
ratings. Our approach does not need any survey data for training. Yet, on
validation against actual survey data, proxy ratings yield reasonable
performance results. Additionally, we offer a new way to draw insights from
values of the value function, which allow associating specific interactions to
their proxy ratings. We introduce two new metrics to represent ratings - one,
customer-level and the other, aggregate-level for click actions across
customers. Both are defined around proportion of all pairwise, successive
actions that show increase in proxy ratings. This intuitive customer-level
metric enables gauging the dynamics of ratings over time and is a better
predictor of purchase than customer ratings from survey. The aggregate-level
metric allows pinpointing actions that help or hurt experience. In sum, proxy
ratings computed unobtrusively from clickstream, for every action, for each
customer, and for every session can offer interpretable and more insightful
alternative to surveys.Comment: The Thirty-Third AAAI Conference on Artificial Intelligence (AAAI-19
Methods of Sentinel Lymph Node Detection and Management in Urinary Bladder Cancer—A Narrative Review
© 2022 by the authors.Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/4.0/).Introduction: Detection of lymph node status in bladder cancer significantly impacts clinical decisions regarding its management. There is a wide range of detection modalities for this task, including lymphoscintigraphy, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, positron emission tomography, and fluoroscopy. We aimed to study the pre- and intraoperative detection modalities of sentinel lymph nodes in urinary bladder cancer. Method: This narrative review was performed by searching the PubMed and EMBASE libraries using the following search terms: (“Transitional cell carcinoma of the bladder” OR “urothelial cancer” OR “urinary bladder cancer” OR “bladder cancer”) AND ((“sentinel lymph node”) OR (“lymphatic mapping”) OR (“lymphoscintigraphy”) OR (“lymphangiography”) OR (“lymph node metastases”)). Studies analysing the effectiveness and outcomes of sentinel lymph node detection in bladder cancer were included, while non-English language, duplicates, and non-article studies were excluded. After analysing the libraries and a further manual search of bibliographies, 31 studies were included in this paper. We followed the RAMESES publication standard for narrative reviews to produce this paper. Results: Of the 31 studies included, 7 studies included multiple detection methods; 5 studies included lymphoscintigraphy; 5 studies included computed tomography and/or single-photon emission computed tomography; 5 studies included fluoroscopy; 4 studies included magnetic resonance imaging; and 5 studies included positron emission tomography. Discussion: Anatomical, radioactive, and functional detection modalities have been studied independently and in combination. The consensus is that preoperative detection with imaging helps guide surgical management and intraoperative detection methods help capture any lymph nodes that may have been missed. Each of these types of detection represent their own set of benefits and drawbacks, but there is currently limited evidence to support any change in overall practice to replace conventional staging.Peer reviewedFinal Published versio
Plasma-Assisted Large-Scale Nanoassembly of Metal–Insulator Bioplasmonic Mushrooms
Large-scale plasmonic
substrates consisting of metal–insulator nanostructures coated
with a biorecognition layer can be exploited for enhanced label-free
sensing by utilizing the principle of localized surface plasmon resonance
(LSPR). Most often, the uniformity and thickness of the biorecognition
layer determine the sensitivity of plasmonic resonances as the inherent
LSPR sensitivity of nanomaterials is limited to 10–20 nm from
the surface. However, because of time-consuming nanofabrication processes,
there is limited work on both the development of large-scale plasmonic
materials and the subsequent surface functionalizing with biorecognition
layers. In this work, by exploiting properties of reactive ions in
an SF<sub>6</sub> plasma environment, we are able to develop a nanoplasmonic
substrate containing ∼10<sup>6</sup>/cm<sup>2</sup> mushroom-like
structures on a large-sized silicon dioxide substrate (i.e., 2.5 cm
by 7.5 cm). We further investigate the underlying mechanism of the
nanoassembly of gold on glass inside the plasma environment, which
can be expanded to a variety of metal–insulator systems. By
incorporating a novel microcontact printing technique, we deposit
a highly uniform biorecognition layer of proteins on the nanoplasmonic
substrate. The bioplasmonic assays performed on these substrates achieve
a limit of detection of 10<sup>–17</sup> g/mL (∼66 zM)
for biomolecules such as antibodies (∼150 kDa). Our simple
nanofabrication procedure opens new opportunities in fabricating versatile
bioplasmonic materials for a wide range of biomedical and sensing
applications
Association of Dietary and Physical Activity Patterns and Hypertension in Western Rajasthan, 2022
Introduction: Hypertension (HTN) is a modifiable risk factor for coronary artery disease, heart failure, cerebrovascular disease and chronic renal failure. HTN affects about 1 billion people globally; by 2025, up to 1.58 billion adults worldwide are likely to suffer from complications of HTN. This study was done to know the diet and physical activity patterns and HTN among the population of three districts of Western Rajasthan.
Objectives: To study the dietary and physical activity patterns among the population of Western Rajasthan. and to compare key findings among three districts Pali, Jodhpur and Barmer so that lifestyle changes can be recommended.
Methods: A case-control study was done among attendees of NCD clinics of tertiary-level centers in Pali, Barmer and Jodhpur. Hospital Controls were matched to age (± 5 years) and gender Considering the prevalence of HTN to be 20%*, the proportion of exposure in the general population as 0.2, odds ratio to be 2.2, power =80%, alpha=5% sample size is estimated to be 102 cases & 102 controls (from each district).
Results: Overall being married (OR= 3.3), having diabetes Cardiac disease (OR= 2.6), excessive salt consumption (OR= 2.7), moderate physical exercise less than 30 minutes (OR=1.9), using oil other than vegetable oil(OR=1.8) , Age >?60 years (OR =1.4) were the key risk factors. It was found that high BMI (BMI>27), consumption of non-vegetable oils (12.7%) was highest in Jodhpur, lack of moderate exercise for at least 30 minutes (81%), lack of sports activity (92%) was highest in Pali, least number of days/week of fruits and vegetables consumption (~1.64 days) was seen in Barmer.
Conclusions: Change in quantity of salt consumption and incorporation of moderate physical exercise for >30 minutes was most followed in control of HTN among the attendees of NCD Clinics from the multiple advise given
Thermal Analysis of a 3D Stacked High-Performance Commercial Microprocessor using Face-to-Face Wafer Bonding Technology
3D integration technologies are seeing widespread adoption in the
semiconductor industry to offset the limitations and slowdown of
two-dimensional scaling. High-density 3D integration techniques such as
face-to-face wafer bonding with sub-10 m pitch can enable new ways of
designing SoCs using all 3 dimensions, like folding a microprocessor design
across multiple 3D tiers. However, overlapping thermal hotspots can be a
challenge in such 3D stacked designs due to a general increase in power
density. In this work, we perform a thorough thermal simulation study on
sign-off quality physical design implementation of a state-of-the-art,
high-performance, out-of-order microprocessor on a 7nm process technology. The
physical design of the microprocessor is partitioned and implemented in a
2-tier, 3D stacked configuration with logic blocks and memory instances in
separate tiers (logic-over-memory 3D). The thermal simulation model was
calibrated to temperature measurement data from a high-performance, CPU-based
2D SoC chip fabricated on the same 7nm process technology. Thermal profiles of
different 3D configurations under various workload conditions are simulated and
compared. We find that stacking microprocessor designs in 3D without
considering thermal implications can result in maximum die temperature up to
12{\deg}C higher than their 2D counterparts under the worst-case
power-indicative workload. This increase in temperature would reduce the amount
of time for which a power-intensive workload can be run before throttling is
required. However, logic-over-memory partitioned 3D CPU implementation can
mitigate this temperature increase by half, which makes the temperature of the
3D design only 6C higher than the 2D baseline. We conclude that using
thermal aware design partitioning and improved cooling techniques can overcome
the thermal challenges associated with 3D stacking
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